The newer games added more transparency and in game ways to find out the stats, which IMO was a good move. I actually like the concept of IV's/EV's in general. It makes the game a bit more varied and adds slightly more depth to things like online battling/trading. Your pokemon gets stronger by battling beyond just leveling up (EV's), and it added some needed depth to breeding (IV's being passed down).

Having it hidden and requiring cheating/save reader/stupid workarounds to figure out the IVS for the first several gens was annoying though.