I have 18 acres 12 of which are under water. My 1710 is about like the
L2501 and it is perfect for a lot of things. I certainly would not go smaller unless you really wanted a lot of maneuverability like getting into stalls in a horse barn. If anything I would go a little larger but I am certainly not complaining.
Somebody said a wheeled tractor is not good around ponds but mine has never heard that. It is around it and in it (intentionally) many times a year.
BTW - a sickle bar mower is really nice for trimming around a pond. Here is a video of mine at work.
Pond Edge Trimming - YouTube