Well, if you end up getting the Dolmar/Makita then converting it to a 80cc down the road then you might still want a 50cc saw, I dunno. I'm not sure how easy it is to do that conversion so make sure you want to get into that before you decide for sure to go that way. Even if you don't convert to 80cc the 64cc Dolkita is a fine saw from what I've read here.
I don't do a ton of cutting so I just use my 346 for everything. It's the only saw I own (besides clunkers that never leave the house anymore). My point is, I never find the need for a smaller (or bigger) saw than that, but I'm not climbing trees to cut and I'm not taking down much really big wood either. If you still want a 50cc saw and don't want to drop the big coin on the 346 later I would look at the Dolmar 5105 (still not cheap but less than the 346). Or maybe the Husky 353 which is similar to the 346 but not quite as high end and definitely a little cheaper and I think a little heavier (but not too bad). The Stihl MS261 is a great saw as many here will attest to, some say better than the 346. I've never run one, just looked at it in the store. I put it down pretty quickly when I looked at the price on the sticker :msp_scared:. Guys in Canada say Husky really jacks up the price up there so for them the 346 would be the saw with the sticker shock.
If you decide you want to go smaller than 50cc I'm not sure what to suggest as most of the research I have done was on the 50cc saws since that was what I was in the market for in the spring when I decided on the 346. I think someone mentioned the MS200 which I have heard is kind of the gold standard in smaller saws but don't hold me to that. Not sure if that would be too small unless you go with a three saw plan and still end up with a 50cc-ish saw as well. Lots of good used ones out there for sure if you have time to look around. If I end up going with more saws I probably won't buy another new one. Glad I did it for the 346 but not for additional saws.