I find the 18" bar on an 026 to be well balanced, and capable of handling 90% of what I come across. Its set up for 3/8". Its a time-tested reliable saw... but....
at 5-6 cords/year, have you looked at the new ms270?...
and have you considered an 025?
The problem I see is that the 029, for all its drawbacks, is serving you well. So you can trade it or sell it at a considerable loss for a similar sized saw that will serve you just as well with room to spare; or you can keep it as a back up, which is always nice to have; or you can go for something outside that range, either up or down. Small saws are nice for brush and limbing/clean-up if you fall any residential trees, and big saws are nice for.... well, they're just nice.
Don't think I'm picking on you. I also had an 029 that gave me few complaints other than it wouldn't cut through rocks. Then the bug bit me, and I brought home an 044 with 18" and 25" bars; followed by my 026. And lately I've been looking at 046's, 066's and Solo 690's which I may never use (but ya never know).
I'm also driving my wife crazy with talk of a decent sized chipper to make mulch out of all the bark and small stuff left over after I split a bunch (using my new splitter, which I keep in my new shed).
You see. What you call a bug, my wife calls an obsession. But I digress...
Think about a range of saws that will give you the best tools for the type (size) and amount of wood that you will be cutting. The 029 was your "experimental", or "training" saw (kind of like that first child). Now you're ready to get down to business, and once the bug bites, accept the fact that one saw is not enough.