>>12414887Yes and no. As far as IQ goes, there's usually a point where effectiveness starts to diminish.
There is an IQ cap, and some groups gain their last skill well before they hit the cap. Gummies will be easier to obtain the further you go on. You'll be able to afford them from the shop easily. Feel free to look up the data on IQ, I won't spoil anything for you.
EXP-wise, it's much easier to obtain EXP in endgame and post-endgame dungeons. You can slide in a weaker pokemon and keep it protected with some strong ones and it will skyrocket in levels. Last time I played I raised up a Cloyster and Xatu and they held their own just fine.
and a quick tip- when you get your first egg and it hatches, take a peek at it's movelist! 