Just thought I'd give some ideas on how to make the sidequest system just that tad bit better.
1) A "battle road" system between regions.
How this works is that between each region, after you do a set amount of battles you'll be able to claim sidequest exclusive pokémon/avatars and/or items like experience boosts and arbokites or snorlaxites for example.
To coincide with the upcoming achievement update, achievements will be given out for completing 25%, 50%, 75% and 100% of the sidequests. These will again, yield rewards obtainable only through these means.
(Apologies if this is in development already).
3) A new Pokémon variant
A new Pokémon variant could be made available after a certain number of sidequests is completed. This will also give people who are close to Pokédex completion a little extra work.
So yeah, that's what I've thought up of, please leave any suggestions/feedback in the comments. Thanks! :)