14 no it doesn't feel slow, it is coherent with 12. But yes, maybe it should be played further since it may end up being too close to white's wall when black takes 6.
16 the standard move/proverb is to invade the 3-3 point when both star points on the sides are already taken. You should be able to get sente and reduce the moyo from the outside or make yours bigger.
28 playing under 15 feels like better shape.
52 unless you've carefully read something, I'd keep the aji for later. For instance if white still plays something like 79 later, you may gain the stones necessary to kill black's group. Otherwise said, as long as there is this aji, the corner can safely be said to be yours. Once you've made black stronger, "your" corner may not be yours anymore.
82 and 84 feel like white has forgotten that the center is key here.
98 unless it kills, taking sente seems bigger.
108 T13 looks interesting.
136 maybe around N/O3 ? White played the high move of N5 and you have a stone at P6, this should be enough to make something happen.
As a general comment, it seems to me that sharpening your reading will allow you to use aji better, reduce/invade your opponents' positions in a more efficient way and take sente when needed (98, 118).
I hope this helps!
