I'm a little bit surprised that I managed this long before doing a Pokemon comic. Long overdue, but here it is.
The feature of exchanging numbers with NPC trainers you battle for rematches later was a great idea, but I always thought it was kind of poorly executed. I can't be the only one who finds it hard to believe that these trainers are just sitting around for weeks without raising their Pokemon at all. Especially when a trainer from early in the game will give you a call after you've collected several badges, foiled the plans of whatever evil organization happens to be in the region, and gone on an adventure exploring the land with your team, and they expect a single level 9 Bellsprout to still put up a good battle. I kind of wish that other trainers' Pokemon would scale with your progress or your team's level, though I understand that doing so might not work out the best either, considering that you can change your team at any time and maybe you'd have a party of weak Pokemon with no trainers to battle them against. The least they could do is filter who calls you based on the average level of your current team or something.
If you like Pokemon and webcomics, I strongly recommend checking out Super Effective
by Scott Ramsoomair, who you probably know as the guy who does VG Cats
. Upon writing this paragraph, I realize that neither of these comics are currently on my links page. If you'll excuse me, I'm going to go fix that right now.