I'm a noob at creating my own recipes so what is considered too much in this case for Crystal malts? 5%? more than that? I love strong ales which seem to use a lot of varying crystal malts from 20 to 120 etc.
As someone said before, for me I think its not having enough experience brewing a specific recipe multiple times to know how .25 lbs of chocolate vs .5 lbs affect the overall taste... or .25 Cara 120 vs .5 Cara 60.
With so many different hops out there also, i'm trying to learn the differences between them by mashing a 10 gallon batch and then splitting it up and boiling each with different hops (amber ale or something) But you can't really do that with the grains - at least not without doing two completely different sessions right?
Yes you can, sorta...
Boil a base malt wort with hops then split into different fermentors and add steeped, boiled, and chilled potions of one or more crystal and/or specialty malts to each of those. Keep notes.
For specialty malts that need to be mashed (say Victory), first mash, then boil and chill before adding. The boil times for those potions may vary, but can be as short as 5-10 minutes. You don't want to caramelize them, unless that's what you're after, like Scottish Ales or Barleywines.