Question: I'm a pretty avid user of SU. However, I spend most of my time there rather than here in the meta discussions.

I would be very willing and happy to become a moderator there to help even more, but I feel that lack of 'meta activity' would hinder that chance.

This isn't a cry for me to become a moderator, but just a general question as to how one can be 'noticed' if they aren't heavy meta users?

Answer: 
Use what abilities you have. Right now you can vote to close/reopen, edit, and retag. Do those things effectively and people will start to notice. You can also flag things for moderator attention to get noticed by the current mods.

**Note:** Do these things poorly and you'll naturally be shooting yourself in the foot.

You'll also want to keep asking/answering questions to get your rep up to the 10k level so you can start using *those* tools.

Basically, just be as generally helpful on SU as possible.
Being active on SU is more likely to get you noticed than being active on MSO. There are relatively few of us that spend any real time here, and everyone gets just one vote for a moderator.