Quoted By:
Depends. If it's a usual game size (one region, maybe a postgame island or something) with 802 catchable mons, that sounds like a clusterfuck. There would have to be insane encounter rates and/or route congestion.
If the game was given space to breathe with all of those available monsters, it wouldn't be so bad. 2+ regions with postgame content to explore and an expanded safari zone would be the only way to make that experience not feel absolutely cluttered, and even then you'd run into the issue of not being able to capture the pokemon you want early on. Not to mention you'd have to hamfist every single legendary in there, the to-do with all of the starter mons, the sheer insanity involved in having every single evolutionary item accessible, balancing the level curve with some of the immensely high levels that Unova mons evolve at...
TLDR You'd need some game designers with unholy abilities and a lot of time if you wanted to make it a fun experience.
