How does shit like perfect IVs even translate into the verse? Seems like overall poke-performance would become circumstantial / entirely dependent on how well you train your creatures.
Anyway, I'd probably want to become a serious trainer early-on. Take on the elite 4, win a tournament or 2, maybe interfere with the plans of a criminal organization or something along the way.
After my adventuring and training years are behind me I think I'll go on one final spiritual journey with all the pokemon I've captured throughout the years. I'll take them back to where I found them and see if they wish to be released there. Either way, I'll do away with the pokeballs -- up to the critters if they should like to continue following me or not.
Once I'm done with that I'd like to settle down just outside of a cozy town, perhaps just overlooking it, with my old, treasured friends, if any still remain with me. I can receive the occasional visitor or bright-eyed kid that wants to follow in my footsteps and regale them with a story or 2. If I'm truly fortunate, perhaps some handsome woman I met in my younger days of travel will wish to settle down with me. We might grow old together, enjoying walks into town, and rekindling that childlike wonder in seeing new faces and creatures as the town continues to grow/receive visitors.