My idea is that if someone went on the maps a found a pokemon they already have it should have like A checkmark or something to show that you've already caught that pokemon. So if your collecting maps you don't have to catch more of the same pokemon!

This would be useful if it showed the quantity, because most of the time you need maps for Lab tasks and you'll need to keep count for example you need 3 Haunters, you find a Haunter it'll say 2 Haunters caught or something, for your original suggestion most of the time you catch everything so if you caught it once it won't make a difference.

pdog2's idea alone I rate 6/10. But if you add phoenix's that's 10/10 for me. It would really help people collecting Unowns.

I like your idea pdog and phoenix. If you combined both of your ideas together and they did that it would be super benifical for people.