Yes, good idea IMO.
I never built the Endless but I believe it is quite useful in early chapters but it's value 'wears off' as you progress.
Prosperity Towers is a must I think. Once leveled up a bit it allows you to have fewer workshops (space saver) by boosting the output of the ones you keep.
I've got through chapters 15, 16, 17 with usually only one magic workshop and a level 30/1/2 Pro Towers. And lots of PoP spells courtesy of the tournaments