5 cartridges - Cello, vdH, Benz, Zu, Hana - what stays and what goes?

Learn how to mount a cartridge for yourself and keep them all until you have had ample time to evaluate each one in your particular system. At that point, you may want to sell one or two, but the decision will be wholly yours.
THIS!!
Mounting and alignment are nowhere near the fearful chore people make it out to be. The first one will take a while as you double and triple and quadruple check everything. But you've got 5! Long before you get to the 5th you will be like the Red Bull F1 team. Okay maybe not 1.8 seconds but under an hour for sure. 

Just in case you don't know, one of the hardest most frustrating things about analog is not being able to hear first hand the difference between Benz, VdH, Hana, etc. I would give my eye teeth for such a chance. This is not a chore. This is an opportunity. Do not pass it by!

Thank you.  I have an Oracle Delphi with Eminent Technology arm.  Actually two tables and arms of the same (Oracle Delphi 1 and 2 and ET-2 arms). Both were recently completely overhauled.to the bone.  So I could run them into my pre-amp.  However, it only has one input for phono.  Let me think about that option.   One challenge for me is the Grasshopper is in the process of coming back after retip and the Zu is new.  I hate to sell them as used after mounting and listening test, versus not touched in a tonearm.

Cello aka Miyabi Standard is exceptional cartridge and extremely rare, but your sample is refurbished with different cantilever (Ruby as you said). Who refurbished it for you? 

If you've got two very nice turntables and 5 cartridges, it behooves you to master the art of cartridge mounting.  Like MC says, it's not rocket science.  And if you don't do a perfect job, so what?  Many who think they do a perfect job probably don't, so you're in good company. The more you do it, the better you will be at doing it.  If you want to be as nutty as the rest of us, you need to be mounting your own cartridges for yourself.  MC is also correct, or at least I agree, when he says that hearing how two different cartridges sound in your own system, where you can go back and forth among several is per se very educational and gets you down the path of finding your own personal nirvana quite a bit faster than otherwise.

I’ll echo what others have said, with the components you have it’s in your best interest to learn how to mount a cartridge (easy) and setup a turntable (really not that hard). It’s not important what others think, what IS important is what sounds good to YOU.