Hi Dean,
I think the fish may be deeper and concentrated around structure. So drop-offs of the old creek bed might concentrate them right now. Casting farther out could help too. So as far as bait, using some 4" golden shiner would be very attractive to the size of LMB you are trying to cull. I've caught winter LMB on them before. They didn't just smack it though, the takes are generally kind of slow but steady moving kind of. My son and I caught one a week or so ago on a 4" bluegill. Took a while to bring some close but they noticed and swam around the bluegill "like sharks" ... at least that's how he saw it. Eventually that BG was history and he was getting a photo taken. But the take was slow and steady when it finally happened. We like to fish a Gamatsu Octupus hook in 3/0 under a balloon filled just enough not to stretch the rubber. This just enough to keep the bait out of the weeds but not enough for the LMB to really notice.
When the day get longer ... so like end of January or beginning of February ... I can't explain it because the temps are usually lower but the bite will improve. I can't encourage you enough to get a little boat to get out there. Don't be averse to using helps like jugs and such either. You've got a lot of fish to catch so all is fair in the culling war. When the temps rise again above 55 the bite will be better still. By the way, winter caught fish are IMHO the very best eating.
As for feeding, I will let others chime on this but its good to hear you have the feeder installed.
