As a B3030 owner (no cab) with a BH80-X, I think you'd kick yourself for buying a "little" BH70-X, if for no other reason than the limited reach. Yes, if there's any limiting factor with the BH80-X it's B3030 weight; a cab or filled tires would help keep it planted if they're options for you (weren't for me). The B3030 has more than enough to power to run the BH80-X, which means in some cases the tractor will be the first thing to get loose when the hoe really digs in. I actually prefer it this way, because there's no question the hoe is giving me everything the tractor can handle, whereas a less-powerful hoe would just stall and probably p!ss me off. No regrets here. Get the thumb! Best $350 extra you'll ever buy.
I can weigh in on options that worked for me on my recent purchase of a M7040. First getting a cab model with air and heat is great and this summer it was a treat to go mowe my 30 acres, recommend that for sure. Next also got the loader option including front hydraulic connections operated from the FEL joystick. Works well for angling the 8 ft snow plow and I am looking forward to trying it out this winter. I had the tires filled with calcium for ballast but i am still looking for more ballast which will help when excavating with the FEL. One of my next projects is to make a three point ballast block out of concrete. Also got the tootbar on the bucket. Agree that is absolutely needed if you do any kind of digging with the loader. Next also got three remotes in the rear. Works very well and can control the three batwing decks on the 15 ft mower separetely. Also got the air suspension seat and I a very pleased with that especially on uneven gound. Makes it much more comfortable for sure. The self leveling option work very well and is very convenient when using the pallet forks. Also got the block heater but not sure that I really need it. Then the CD weatherband radio is great also and the rear viper option will allow me to see in the winter.
I amm looking to get a couple of Thumbs for the bucket now from Tatro which will give me much more flexibility in picking up things. Cheers