Ah I wish I could truly justify getting into tractor shopping mode. I will live vicariously through your tractor shopping mode instead.
Both those tractors will do nicely in your setup. I have a 26 acre horse farm with a Kubota L3400 HST - 14 acres of pasture to bush hog. Smaller driveway and trails than yours.
For the L3240, DON'T consider anything other than the LA723 loader with a QA setup. For a small price difference you get 50% better loader capacity. Similarly for the JD 3320 go with the CX loader and get the skidsteer QA.
Both will work quite well with your grapple. I know that the JD comes with a nice diverter setup as a factor option. I imagine you can get the same on the L3240.
On the BH I would personally go with the Woods BH90-X. At the very least the Woods BH80-X. I've been looking at the BHs my L3400 can handle and BH80-X is the max and I'd be happy to take it to a future L3240 with me. I also like the JD 447 and the Kubota BH90. Definately move up from the BH70-X.... again for the price difference it is just not worth going with the smaller ones if your tractor can handle it. If you are like me and only doing very occasional BH work, I think that a BH-80X or a the JD 447 will do just fine.
I have not looked at the JD 447 specs vs Woods but on the Kubota I think that I would get Woods vs the OEM backhoe. I believe it is stronger - at least was on the BH-80X vs the BH75 (Kubota equivalent for the L3400). I think Woods is an awesome company. They have always responded to email - me asking questions about their equipment - pronto - and resolved any issue / question quickly. Probably the very best company building in the CUT or implement business for customer service in my experience. If the specs matched out, for this reason alone I'd go to Woods vs. JD - but that is my own bias.
Personally I prefer the L3240 to the JD 3320. I recently thought about trading my L3400 for a L3240 or L3540 or equivalent. For no good reason of course (which is why I haven't done it). I also seriously looked at the JD 3520. Both are nice machines but for some reason I much preferred the fit and finish of the Kubota. I can get a JD 3520 for a good price because JD does not have issues with me importing from the USA. OTOH Kubota prices here are still to high for me to consider the trade - I'd pay $10 K more at this point to move from a L3400 to a Kubota L3540 w. LA723 loader and as much fun as it would be - it just isn't justified at the moment.
I was turned off by the MADE IN CHINA stamped on the JD's loader which was the first thing that I saw when I got on it. Is this bias... probably. JD sources it so it is probably just as good as any... but we are all biased in one way or the other. I just think that no one I've ever heard of went to chinese stuff for quality - always for price. Does not mean quality can't be equivelent but it is a turn off for me. I also didn't like the plastic hood of the JD.... just me. I'm no fan of plastic.
I would consider dealer support very very seriously between the JD and the Kubota in your final decision.
If you have hills on your property - consider the move in HP to a JD 3520 (turbo) or a Kubota L3540.
In general - I would MUCH rather go with a Kubota L3240 with a LA723 loader and a BH90-X than a L3540 with a LA513 and a BH-70X.... and you will probably find the price difference between these two setups equivalent (if not cheaper to go with the L3240 setup).
Overall, you are comparing two first class machines and can't go wrong either way.
