Welcome aboard! Consider getting something a little heavier built, even if it's used.
Personally, I'd look at anything with a diesel as they seem to do the same work with 1/2 the HP and use 1/2 the fuel doing it.
I got frustrated with frequent engine issues on our Craftsman and decided I needed something more ruggedly built.
Our Kubota G5200H with 14 HP and a 44" deck makes our 21 HP Craftsman with a 42" deck seem painfully underpowered, especially in any grass over 6" long. The Eaton 1100-046 HST unit is smooth and seems to be rock solid. So far, I'm into it for about $2300 ($2000 used price & $300 in parts) and I'm very satisfied.