leaddog:
I'd have to disagree with you on the PTO driven backhoe.
First off, the pto pump is not a pain to deal with. It's just a matter of snapping it on and off the pto stub. They come with a snap coupler, just like any pto driven implement. The other difference is the torque reaction arm that will rides against the draw bar, but that bolts to the pump body, so it's one part to attach and remove.
I agree that most CUT's in the upper range have enough internal pump capacity to run all but the biggest hoes, but you certainly don't have to your pto at rated rpm with an external pump to operate the hoe. On the contrary, the external pump will have more, appreciably more capacity in GPM than the internal hydraulic capacity of the tractor. Hence, the rpm of the PTO can be kept at much less than the rated rpm of the tractor.
Lastly, in my opinion, I'd rather have a separate hydraulic system for the hoe. I have ruptured hoses on my hoe and lost fluid rather quickly. I was not shackled with the worry of draining the tractor's hydraulic system. Besides, the hoe uses normal Hy Trans fluid, while my Kubota uses expensive UDT fluid. In addition, the tractor does not have to absorb the inherent heat of the hydraulics on the hoe. The tank on the hoe absorbs the heat.