sup chickens and hens
I've always preferred cash, but like to mix it up sometimes when I'm bored such as playing sng's and mtt's, including my weekly live mtt (freeroll / satellite) I play at my local bar. I usually don't have a problem getting ITM, but particularly online, I find it hard to get very deep, in anything more than a 90 man tourney on average. I'm comfortable FT'ing on 45 mans and lower somewhat consistently.
I've read a lot of compiled threads on mtt's in general, and apply lots of theory into use which I can tell has helped, but I find my biggest problem is that when I do finally get ITM, I'm shortstacked and have been bottom feeding for so many levels. The people who I see do well in these micro mtt's, especially the large scheduled ones, are by early aggressors who get massive early leads. When I try to play in that sort of low level, early aggression action it obviously doesn't work out the way these Russians, Spaniards, and Portuguese make it happen.
I feel that there may be a general problem with the way I play, since it's pretty consistent ITM but not consistently deep... Is there any big tip or direction someone could put me in here, please?

keep reading. and I'm neither a chicken or a hen

Yeah.
Watch ALL the aggrotards, not just the ones that get massive early leads.
They spew as a group but often to each other (so few group survivors but with big stacks)
It doesn't mean the guy with the big chipstack is a good player.