Yeah, I would rather have the non glowing, more easily destroyable BF1 mines to the glowing BF2 mines, but keep the engineers ability to disarm them with the fusion cutter. Time bombs and Det packs should also be shootable in my opinion, I know you will rarely use this, but there are certain situations, I'm thinking of a time in SWBF1, I was getting into a snowspeeder and some guy planted a time bomb on it, I just jumped out shot the bomb quickly and took off. Sure it's obscure, but it's nice to have the ability.
Also I would also say increase the amount of mines back to four, three just seems like too awkward a number. It might seem a bit overpowering, but I think it would balance out with the ability to shoot mines, any mines just throw without much thought would probably be located and destroyed.
Maybe they could give the engineer class some sort of mine detecting ability? Like mines glow for them only, or they can see them on the mini map, somthing a bit more realistic then mine immunity, to sort of help balance out the engineer class and mines as well.
(actually, I would be for giving mines to the engineer class in exchange for some other items, and giving the Heavies somthing else in return. I just sort of feel they fit the engineer class more then they do the Heavy, but that would require alot more tweaking and balancing, the current layout is probably for the best.)
Not being paranoid doesn't mean someone isn't trying to kill you... or does it?