Originally Posted by
TotoMok
There is no requirement (nor expectation) to upgrade all your specialists.
Smart man realizes how hard it is to make books, and picks and chooses what he upgrades. That is part of the challenge of this game: To make the smart decision.
Me, I made a smart decision: Don't waste books in specialists I don't need, keep a reserve of books so I can upgrade Generals/Island, and use Glue like crazy (which I bought on TO). I'm up to 9 fast explorers and 3 luckies fully upgraded with 100+ books in reserves. By the time General Upgrade comes out I should be able to upgrade all 3/4 generals (MG, 2xMMA, and another MMA possibly). (Why waste books on normal generals, they will/should never be as good as an MG or MMA)