IMO
4.e6 - opening a3-f8 diagonal for your bishop and h4-d8 for your queen
5.h3 - Karpov recommends the move in his CK book to prevent knight pin, but he emphasizes it is playable only in certain variants of CK - I'm not sure if this one is what he meant; perhaps your opponent wasn't sure either?
5...Nf6 - a good question - let me know if you find the answer :)
10...Rc8 : 10...Ne4 - the latter was aimed at restraining white f knight and forcing his retreat that would cramp white position, IMO - I feel I particularly might be wrong here (10...Ne4 11.Nxe4 dxe4 12.Nh2 (12.Ne1)(12.Nd2))
23...etc. - well, we humans hardly match the computer's precision in the endgame, unless we are GM's.
Mind, my rating is about as high as yours, I am far away from a fairly good player, so take everything I wrote with a grain of salt. Just my 2 cents.
Though I made no major blunders, in the analysis its constantly suggesting slightly better positions that increase my lead by .1 or .2. I feel like i'm missing some major conceptual ideas, and its hard for me to figuire out why certain moves are better alternatives than others. I would appreciate any comments or suggestions, especially those that may point out major conceptual flaws I have in my game. My opponent and I both made so many questionable moves that I don't feel like I really earned it. Thanks