When I was somewhere between 13 and 15 (I don't recall exactly and I ain't old enough for this C.R.S. yet...) Dad bought bought an O39 and it was the only saw we had outside of Grandpa's Mac 35 (think hand-held trencher). It was our only saw until I bought my old 55 Husqvarna at 16-17. Those were then all we had until I found A.S. We then bought a 346xp and a 660. ALL of them were great saws and made me a bit of money, a lot of muscle and a fair bit of work ethic at 10-15 cords/year. Once I got a bit smarter about saws, I muffler modded and re-tuned that O39 and it found a new gear. It wouldn't quite keep up with WOLFCSM's 311 (or most of the rest of his toys for that matter), BUT it would pull a 20" bar in Hedge with authority. I would wager that it pulled better than my 562 does now by a decent margin in 18"+ wood. They have all since burned up in a truck fire, but I'd do it all again in a heartbeat. The 290/291 can be found on many if not most farms/ranches in KS. They account for a lot of heating and Hedge posts for assorted fencing needs.
The 291 isn't bad at all and will likely do what you want. If you get rid of the Echo, the 290 would be a good saw for you. If you keep it however, do yourself a favor and buy a 60-70cc saw, even if it's a mid-grade. A 311 can become a 391 and with a M.M, can be a very solid performer. That 660 would be a "Stihl" of a deal at $600.00 as my old one with the exact same 2 bars and a hand-full of chains each, was a bit over $1300.00 after taxes. It might be a bit more than you need, but you might be surprised. The last time I was in Buena Vista and the Cascades outside of the Mt. Princeton Hot Springs, we had to clean a few trees that the state said had to go on Dad's land. Of those four saws I had, the 346xp and O39 went, because that's all I needed. I would bet that a good 60-70cc saw with a 40cc backup would do a lot for you. See if you can find a John Deere (Efco) CS62 and if not, I'd also look hard at the Echo 620P as a few farmer friends have them and like them very much and most of the wood we cut is a bit harder than Pine, Elm, Ash and Spruce. It's the same price as that 660 and that new 261 but it's more manageable than the former and more capable than the latter.
I guess what it comes down to is size: If you're hiking in a ways and/or not cutting over 30ish inches routinely a good 60cc saw (or 70 for the right $$$) might be the way to go. If you're routinely seeing 30"+ stuff and not hiking a lot, 70+cc is Definitely the way to go. If the bigger logs in your picture are the exception to the rule/or you're hiking a lot and normally bucking 20" and less dia wood, a strong 50cc saw will do you fine. Ultimately what do you "normally" intend to cut and how much. 50cc is for 16" and less in hardwood (although they will do more). 60cc is for 12-24" wood, 70-80cc is for 20-30" wood and 90cc +/- is for 28"+ wood for me anyway. For Soft wood, the sizes can slide to the right a bit. The other trade-off (generally) is that as the displacement of the saw gets larger, it's cutting speed is inversely slower, until it's cutting beyond the limits of a lower capacity saw. M 372 with a 7-pin rim would spank my old 660 with a 7-pin, until it gets to 28"+ wood. That's where the 660 shined. Change the sprockets and things change bit though.
I apologize for the novel, but there seemed to be a lot of 290/291 bashing/praising and not a lot of honest capacity perspective for your consideration.
Have a great day and good luck with whatever you decide!