1*I love the "toy" put down. I'd challenge anyone who thinks a BX24 is a toy to go one on one with that machine while armed with a shovel and a wheelbarrow.
2*On a 3 acre plot of land, if ground clearance is not an issue, a BX size SCUT is more than adequate and would do a much better job mowing, which is likely the most common task, than virtually any other size tractor. Slightly used BX24s with less than 300hrs on them go routinely in my part of the country for under 13 thousand. Fabulous deal for a newbie with 3 acres.
3*Wish I had one to supplement my 40hp machine.
If you spend you money on a smaller tractor you can have more implements to accomplish tasks than if you invest in a bigger engine and more iron to contain it than is really necessary. For example, with less money you could have a SCUT with a grapple bucket that would carry way more debris than a 40hp tractor with only a bucket. With a BX24 you could have BH and mower mounted simultaneously so
4*
you have an all purpose machine rather than waste time dorking around changing implements.
5*As someone who started with 20hp and moved to 40hp, I have first hand experience with the pros and cons. The 40 clearly does things I could not do with the 20 such as pull out a stump in a single motion with the much stronger loader. But, I was able to get the same stumps out 5 minutes later with the smaller tractor, it just took a little intelligence and time to replace the lost muscle. If I were in business I'd easily justify the bigger tractor but as a homeowner in this situation the smaller machine just makes a lot more sense. On the con side of big, consider costs and storage of bigger implements, heavier tractor to leave bigger ruts, inability to get into small spaces, being further away from what you are doing so being less accurate, more fuel per unit of work, more oil/tranny fluid costs at service time....the list could go on.
Here are some things you can do with a wimpy toy 20hp tractor. Match them with your spade and wheelbarrow.