Do yourself a favour, and bite the bullet with InDesign. It is not that hard
Photoshop is OK if your making a print, but even if you keep dpi high, it is not good for PDF.
The pdf has the resolution you set when saving the pdf (provided the original file provides as much).
If text appears pixelated in the pdf then you may have applied Faux Styles (like faux italic) or Layer Styles to it or the font itself may have issues.
Text and vector elements should result in vector data in the pdf.
Can you provide screenshots/examples?
I know that Photoshop is not the premier pdf creation software. I do have InDesign as well, but I'm much more familiar and comfortable with Photoshop (I have the CC versions of both) so I prefer to use it as my design and layout tool.
This is kind of like saying "I know that a screwdriver is the correct tool for inserting screws, but I'm much more comfortable using a hammer, so I prefer to just hammer the screws in."
It works, sort of. But the results will never be as good. And you wouldn't want to use the screwdriver with nails, either. There are two different tool (programs) for a reason, and I think once you learn InDesign, you will find it to be a much better layout tool than Photoshop.