This may be way too big of a request, since Serebii is a big site and I don't really know the logistics you're with. And it's probably something that's already been considered, but:
A more mobile friendly site would be nice. Either a mobile versions or making the current one responsive. (talking about the actual site not the forums)
Pokemon being a portable game and all I am sometimes playing it when computer access isn't possible and being able to smoothly and quickly look up important information as I am playing would be a great feature.
It looks like you have already fixed some things, I noticed the pokedex works better on phones now, I was having some issues last year with it, but the drop down menu functionality seems to have changed for the better.
Random Pokemon Fact Of The Day?
Then there would be something everyday.
And for the Moveset Calculator, I think there should be an ability filter (to search for stuff like Baton Pass Speed Boost).
In the Pokedex, is it possible to add the sprite from the back?
A random page button to send you to literally any page, even very old ones, randomly.
In the IV calculator, I'd like it if we could enter more than one best stat and also worst stats.
In the ItemDex, add EXP Share to Key Items, since it's one in Gen VI.
They didn't give a reason why this thread was locked. Whatever the reason was, even if it was listed in the rules shouldn't it be posted why it was locked? These kind of warningless locks puts questions up on Serebiiforums users. Thank you. I didn't mean to offend anyone and was giving my honest opinion.
And also we want colors, bolds, italics, everything you can do on VMs to be done in Bios. It would spice up a person's bio.
I'd like to see Legendary Pokémon pages updated with what happens if you defeat them or flee from battle. Base stat totals listed for pre Gen VI Pokémon pages like in the Gen VI ones. Gen IV evolutions removed from the Gen III pages (and similar occurrences that are probably in Gen I and Gen II pages).
This may just be me, but I've always thought it'd be nice if there could be a notification if someone just replies to comments you make on threads. I know we have the whole subscribing thing, but I think it'd be easier to just have where you'll get a notification if someone replies with your comment in quotes, or something like if you get mentioned in a post.
I think there should be a link to the POTW on the pokedex page of Pokemon that have POTW.
Darkrai has a link in the XY dex to the 6th gen POTW and a link in the DPPTHGSS dex to the 4th gen POTW.
On the #th gen dex, put a POTW link to the respective gen POTW.
Hey, Serebii. Do you plan to make an OR/AS style themed after Primal Groudon and Kyogre (maybe also Rayquaza?)? It would be neat to make one, been waiting forever for one after the Hoenn remakes announcement!
Also, is it possible to make avatars for all playable characters in the new Smash for 3DS and Wii U? Thanks.