I like the limitations as well, but if they limit it anymore, I'll be sad. I was a fan of it, but knew it's OPedness.
The Jet Pack was for reaching higher places, not a single-and-a-half jump. As long as I can't trick jump as high as I can Jet Pack, I can live with it. I do think that Jet Pack's recharge shouldn't be overly long, but definitely longer than Reach's. So far, 343 is trying to set it in the right place and is almost there, if not already there.
I do disagree with one thing, however. Jet Pack should not seem like a vertical Thruster Pack. IRL, Jet Packs are used to hover and fly, and in combat, I can see it being reduced, but not to a simple single boost.