Hiya Basic, welcome to TBN.
Neil Messick gave you some great advice. Based on what you've told us, the 3430 is the smallest I would go, and the 3830 will give you more torque per HP due to the longer stroke. He also gave you a good steer about loaders; if you can get by with the 753 loader, the 3830 is a great choice. If you want more loader, a 4330 with an 853 is an animal. I don't recommend the 4630 because it has the same torque as the 4330. That leaves the 5030, which has more 3PH lift than any of the Grand L's, and is physically the largest, but might just be overkill. The beefy front axle does allow for some awesome load-handling ability though, especially with a heavy implement on the back.
I think the Grand L's are an excellent value - I paid $24,950 for a 5030HST with 853 loader, HD bucket and quick-attach. Speaking of HST - I'd encourage you to seriously consider it. When working in the variety of conditions and terrains that you'll encounter in commercial work, the control that it gives you is amazing. The GST is also a beautiful transmission, but I much prefer HST for the types of varied tasks you describe. To me, the only advantage of FST is lower initial cost.
Good luck with whatever you end up with; while my gut feeling is that the 3830 might be your best bet, I think that any of the Grand L's would get the job done.
John D.
PS The "search" function on this site is incredible. With over 800,000 posts you could read about Grand L's for about 2 years and learn so much it would truly make your head spin. Good luck, and feel free to ask a lot of questions. There are an awful lot of helpful and knowledgeable people here.