I have two different questions about power and I'm not really sure where they are newbie questions or something for more advanced players!?
First off, is 30 infantry range units worth more power than 30 infantry armor units because every I always find that I get loads more power when I recruit range or damage units?!
My Second question, I was wondering if there was any way other than a spam from which I could find out whether my opponents are recruiting armor, damage or range because the difference can cause a big changes at war and some times I don't always have the timeto spam first!

I think Mm asnwered ur second question pretty well.

with ur first question, I can guess that when u do all armor, ur worker will lose more compare to when u recruit a good ratio of range and/or damage (since armor cost less u can recruit more), to one point ur resource will be noticably less than when u recruit range and ur recruiting will have to be slowed down.