The short answer is a powerful desktop!
I have tried the whole laptop Premiere, Ae, Blender melarky and generally found it to be usable but not brilliant. For Ae, get a powerful CPU and as much RAM as you can (16GB+) (swap out the RAM yourself to save some money - assuming you don't buy from a certain tech giant with a recent love for soldering on and gluing components and back cover to make everything non-user replaceable...). GPU does not have as much of an impact as you might think for AE, so prioritize your spending elsewhere. Also look for laptops with either a second hard drive bay or optical drive bay (in latter case remove optical drive and buy hard drive caddy to fit online). Goes without saying, but replace out primary drive with SSD (though if laptop has HDD as primary drive, warning bells should be going off about where else OEM has skimped).
As long as you have good internet 99% of the time when you would want to use your laptop, my personal recommendation would be to get a laptop that is light, portable, with very good battery life and a great screen and forget about doing video work on it directly. Instead install a remote desktop app/program like TeamViewer, and use it to view screen of desktop at home and edit that way. Coupled with the WakeOnLan protocol, you can just resume desktop from sleep remotely when needed avoiding worry of having desktop on 24/7. This will give you a far more powerful setup, save you some money and make your system truly portable (no continual battery anxiety, very heavy laptop bag; all for a barely powerful enough editing experience - had to look at proxy editing for some projects. Just personal experience.).
I should add, remote desktop technology has improved huge amount over past couple of year but it does still need a fast upload and low latency connection at your desktop end. Do a test run before you invest your hard earned money into a solution that may not work for you!
Of course a desktop is better, but if you do need a laptop, I have the Dell Precision 5510, which works really well. Check it out, it has an optimizer tool that really works!