Hi Slick,

I find I play different guitars differently, depending on their style, strings, etc. You certainly don't want to choke the guitar so hard that it wears out your hand muscles. And you don't want to strum harder than the guitar itself can handle. If it seems to be rattling from the impact, compromising the tone, you may be overdoing it a bit.
I actually wham on my acoustic with more gusto than my electric, because the strings are hardier and it responds really well!