The size of a PDF saved from Illustrator depends on many things, but in this case, what options did you use when you saved? What preset did you use?
Illustrator files can be large, especially if they contain many images (linked or embedded) and are saved with PDF compatibility. This option can be changed in the options dialogue that follows saving a new file or doing a Save As. Illustrator saves the data in two formats within the same file: once as a native editable Illustrator file and once as a high resolution PDF for printing, rasterizing in Photoshop, or placing in InDesign.
If you don’t need to work with the file outside of Illustrator you can turn off PDF compatibility and save quite a bit of space. I was once archiving for artwork for hoarding (the large signage around a condo development). The designer has not changed the save options, so all linked artwork was included in the PDF portion of the file. I turned that off and turned a 200 MB file into a 1.5 MB file.
As for your follow up question: Note that Illustrator cannot export a PDF. It saves a PDF. This is not an insignificant difference. If I am editing “Logo.ai” and want to send my client a proof I must Save As “Logo.pdf” setting whatever options are appropriate, such as low resolution images and Illustrator editing capabilities OFF. If I continue working on the logo, then save and shut down, all work I did after initially saving as PDF will be lost, because I did not save an Illustrator file. This is a terrible mistake on the part of Illustrator’s developers and has likely cost many companies millions of hours in lost work.
The work around is to either immediately re-save as an Illustrator file after saving as a PDF or to use Save a Copy, which further requires editing the filename to remove the pointlessly added “copy” from the filename.
I tried disabling the "Preserve Illustrator Editing" and that brought the file size way down, small enough to email. Also, you're right about the "Save a Copy" After I tried that it saved the pdf to my desktop but kept my original Illustrator window open, which is exactly what I was trying to accomplish.
Once you do a save as to .pdf, the file on screen can be saved back to a .ai and all the layers and everythign wil be as normal. I belive that is dangerous, incase you have multiple files open, and forget if it was opened as a .pdf or as a .ai file.
I personally use an action to save the file, then save as to a .pdf to the desktop and close the file afterwards. If you save your .ai files with pdf compatiblity turned off they open quickly.
Only problem I have with this workflows is the actions goes so quick, that illustrator can crash occasionally. I set playback option in the actions palette to 1 sec and that is fine. But I have to set that setting every time I boot Illustrator as it is not persistent.
There are things I like way better in FreeHand...
live manipulation of stars and polygons
Geometric primitives, otherwise known in the old days as LBOs (Lines, Boxes, Ovals, but includes arcs, stars, polygons, etc.) in Illustrator have never been created as special objects with live geometric parameters (corner radius, number of points/sides, angular sweep, etc.) as they are in just about every other program on the planet. In Illustrator, they are just created as lame ordinary paths. One of many very very basic standard functions taken for granted everywhere except in Illustrator.
...simpler tools for beizer curves...
More precisely, the archaic and cumbersome interface Illustrator applies to selection (in general, not just paths) in combination with its unnecessarily tedious multi-tool routines for manipulating Bezier paths, in combination with its inconsistent interface display logic. FreeHand's interface for this remains best-of-class. Illustrator's remains worst-of-class. Everything else is somewhere in between.
…3D effects are live and don't require a secondary window…
Illustrator's 3D Effect is an entirely different featue from FreeHand's 3D Extrude. Illustrator's 3D Effect actually calculates 3D geometry; it builds an actual 3D model. FreeHand's 3D Extrude is an arguably clever, but strictly 2D "perspective" kind of construction. There is no actual 3D involved in FreeHand's 3D Extrude feature.
As for the modal dialog: Illustrator is chock full of them. One of the dead giveaways of an archaic, outdated program. So 1980s. But the one in 3D Effect arguably makes sense, because 3D Effect is a plug-in which actually is a subset of the functionality of an entirely separate and discontinued program (Adobe Dimensions).
…type on a path is much easier…
Just wait. That's just the tip of the Illustrator text-handling iceberg.
…a pdf…ended up being 25MB.
This is all part of a mostly smoke-and-mirrors marketing ploy that Adobe (owner of Illustrator, PostScript, and creator of PDF) perpetrated upon the industry a decade or so ago in which it proudly proclaimed "PDF is now Illustrator's native format!"
It's a semantics game in which Adobe basically tries to redefine commonly-understood terms like "native" and "file format." In fact, only the basic constructs of Illustrator objects are understood by PDF. For practical purposes, all the former ballyhoo about 'Illustrator and PDF being the same thing' boils down to this:
By default, when you save an Illustrator file, Illustrator writes an entirely separate version of the content as PDF and "tucks it away" inside the resulting file. That's one large chunk of what makes Illustrator's files look so inappropriately large. Other Adobe programs read the PDF content and ignore the actual AI-native content. So, for example, InDesign's interface scheme pretends that it can place an Illustrator file. It's really just placing the PDF content that is tucked away inside an Illustrator file. Save that "very same AI file" with the PDF Compatibility option turned off, though, and InDesign will not be able to place it.
Inversely, Illustrators interface scheme now pretends that it can Save a PDF as opposed to the normally-understood meaning of exporting a PDF. All this means is that by default, Illustrator writes into the resulting PDF an entirely separate version of the content as Illustrator native objects and "tucks it away" inside the resulting file. So again, you end up with an absurdly bloated PDF. Programs other than Illustrator read the PDF content and ignore the actual AI-native content. Save that "very same PDF file" with the Maintain Illustrator Editability option turned off, though, and when you open it again later with Illustrator, you'll find that everything has been dumbed-down to the simpler and more basic constructs that PDF actually handles, contained in a bunch of (often nested) clipping paths. In commonly-understood language, you have not "opened" that PDF; you've imported it.
It's similar to what Macromedia did with PNG and Fireworks. Fireworks doesn't even give its native files a unique file extension. It's "just" PNG. But in commonly-undertood terms, it's not just PNG. The PNG format was written to accommodate a mechanism by which a program that writes the PNG can "tuck away" or "comment out" or "embed" anything its own content. So when Macromedia built Fireworks it just built it to write all its own native stuff (for example, its vector paths) in that "embedded" region of the file, and still save the file as a PNG. So—PNG being the raster image format that it really is—someone uses a raster program (Photoshop, etc.) to open a PNG that some unsuspecting Fireworks user created thinking it's a vector/raster metaformat (after all, PNG is Fireworks's "native" format, right?). The Photoshop user makes some minor edit and saves the PNG. The Fireworks user opens the file and wonders where all his Fireworks-native vector objects went.
Adobe, of course, acquired Macromedia, discontinued the vector program with which it could never functionally compete, and kept the web-centric drawing/painting program Fireworks. But of course Fireworks didn't handle the smoke-and-mirrors the way Adobe did with Illustrator. So now, in the most recent versions of Photoshop, you receive an alert when you open a PNG that says something like "Contains Fireworks content that will be lost when you Save this file." Real elegant, huh?
Such nonsense and confusion is what results when programmers are pushed by marketing to over-insulate the click-and-drag users from what is really going on.