Tower tactics.

That's a good point. Especially considering that giants are the only tier 7 unit that can actually be built by the end of the second week.
Well, if you prefer to build them at the end, that's a matter of taste...

I try to build mages and gremlins as quickly as possible because they require few resources and are good ranged units in the early game. As for the Mage Guild (level 4) + library, it's mainly for Chain Lightning (if not Soulfire), Resurrection, and the Town Portal. You can also use Berserkers and Lightning spells. And you're right, it's very easy to build giants in this castle, which means you can