Thanks for the input! Here's my view...
Tiers: I may add these at some point. They are mainly opinion but can be a useful guide.
Pre-evolution: Done. See http://pokemondb.net/pokedex/sceptile and http://pokemondb.net/pokedex/609 for examples :)
Event moves: I want to get these up at some point. You're not missing much since there aren't very many of them.
Arrows: I'm working on something. Prev/Next on its own isn't all that useful so I think I'll combine it with a quick search/dropdown thing.
Stats: We'll have to agree to disagree on that one. I find Serebii's stat box difficult to read, with tiny numbers all over the place.
I don't think you really need to know, e.g. the highest value for a hindering nature. we have the base stats, the absolute lowest and absolute highest. IMO that's a better guide.