From what I've read here, and from what everyone always says "no one ever says I wish I got a smaller tractor". That said I would say from what you describe you'll be doing: go for the smaller tractor. From what you describe above, there is nothing the 23S cannot do very well, and at a price point that will allow you to get a few more attachments right away over a B series.
I took my tractor home and started lugging pallets of patio stone around with it, maxing it out every time, from ~500 pounds out at the arms and ~700 pounds at the curl point. I thought to myself the whole time, man this is great but I sure wish I had a bit more tractor so I could lift at least 1000 pounds. But now that I'm done with that job I'm sure I'll be loving the unit completely, and I do.
2 properties = transporting it as well. I'm very happy my tractor fits nicely on my EQ trailer. It's main job for the next year will be tearing up 700+ feet of curbing at our office, trenching and replacing with curb stone, which is the main reason I wanted the hoe in the first place. Not paying someone $20,000 to do the job means the machine pays for itself right there....then I get to keep the machine for future jobs.
If you have a well manicured lawn like I do, I have a 1.75 acre lot, 3/4 of that is nice grass, I would strongly recommend against using any of these with a MMM. I didn't even buy a MMM for mine, don't intend to, I have a zero turn. But the real reason: the 23S is 1600 pounds and the turf tires act like a steam roller over my lawn. When I built my patio, the tractor tracks back and forth compacted the soil down so hard it was like concrete, bad for the grass. I cannot imagine mowing with one of these all the time. You'd need to mechanically aerate 3 times a year if you wanted a nice lawn. Even at that rate it would not work.
If you see yourself with pallet forks wanting to lift 700-1000 lb objects a lot, the 23S is not for you, otherwise, I think it's the perfect little tractor for what you describe.