Simple answers to complex questions.

Well, I haven't played the Academy much, so I don't know all the nuances of developing this faction. In terms of regular resources, this Castle focuses on ore; wood is mainly needed for building high-level creatures (and for upgrading some mid-level creatures). Only ore is needed to build Gremlins and Gargoyles. So, the first thing to do is to take an ore mine from the neutrals. The Gremlin upgrade became more accessible in version 1.3; now it requires 5 ore instead of 10. The upgrade turns them into better Tier 1 archers (initiative increases from 7 to 11, several other parameters are noticeably improved, and the ability to repair is added), so the sooner you do it, the better. Gargoyles... they protect Gremlins well and block enemy archers. Golems are slow but well-protected warriors; they are most effective when supported by Elder Gremlins (Gremlins can repair Golems; 1 Gremlin restores 5 hit points). Upgrading Golems is very important; it makes them much more effective. The principle of capturing ore on the first (second) day is the same as for all factions: buy a second hero in the tavern and give him the army to support the main hero. I honestly don't know who the favorite hero is among the Academy heroes right now. It's best to ask experienced players of this faction which hero to choose, which skills to upgrade, and how to develop after capturing the basic resources