It all comes down to HP needs of the item being driven. Keep in mind that gearing is the issue here.
When one of our tractors is used to power a deck or snow blower, the belt coming off the PTO is usually spinning those attachments at actual engine speed or very close to it. In other words, the engine RPM is geared up or geared down only a few hundred RPM at the most to spin decks and snowcasters. The 540 RPM speed of the L29 PTO is the result of a 6 point 66666666666 reduction of the 3600 RPM engine speed and that reduction multiplies the engine hp and torque by that same factor theoretically. However, many of the attachments that are designed to be driven by the 540 RPM PTO shaft of a full size ag tractor, have to be "geared up" by the same 6.66666 factor because attachments like a genset or water pump were actually designed to spin at 3600 RPM when they were initially designed.
Someone just adapted those items to work as a 540 PTO driven attachment instead of having a 3600 RPM engine driving them. So, on one end the L29 looks like it multiplies that 14 HP K engine by a factor of six and two thirds but in reality, there is a net loss due to the two gear boxes needed to change the speeds from fast to slow and then from slow to fast. On one end the L-29 is dropping the 3600 RPM engine speed of the Case GT to 540 RPM but there's a gearbox on the end of the PTO shaft that connects the L-29 to the attachment that speeds the 540 RPM input speed back to 3600 RPM once again. The wiser thing to do would be to forget the L29 and just make up a mule bracket that would allow you to directly belt drive a generator or water pump. It would be far more efficient to do it that way for some of the attachments that are designed to be run by a 540 PTO.
So yes, you can power bale elevators, grain augers, some standby gensets, water pumps and so forth but the question becomes one of torque if the device being powered is asked to deliver "full load capacity". As an example, a genset capable of delivering 4500 watts constantly may run perfectly when the load is only 4000 watts but when the load increases to 4500 watts, the engine of a Case GT may slow down due to lack of HP/torque. If it slows down, then that interferes with the frequency of the AC produced because 60 hertz or cycles per second is a mathematical component of 3600 RPM (60 X 60 = 3600)
A water pump might also work well if it is used to just drain a pond because there is no "head" involved and the water output is not being pressurized by nozzles designed to shoot the water long distances for irrigation purposes. The pump will pull the water out of the pond and deliver it hundreds of feet away as long as the discharge hose is just laying on the flat ground. Now if you run that discharge hose up a hill that is 40 feet higher than the pond, then the weight of that 40 foot high column of water will push back against the pump, making it work much harder than if the line was either laying on flat ground or running down hill from where the pump is positioned.
In other words... just because you own a 448 and an L29, that doesn't mean that it will power every 540 RPM implement on the farm. Or..... while it may run them, it may not run them to their maximum rated output due to a lack of HP/Torque. However, if you were to delete the L29 and the gearbox on the implement and just direct drive that attachment with a V belt, the full output might be realized because the engine doesn't have to overcome the losses created by the two gearboxes.