As lazy as this sounds, being able to control volume remotely is quite important.
In my situation. What would be the most efficient way to do this? Do I get a preamp with a remote and connect that to the Elekit with the Elekit volume maxed out?
There are a few passive remote volume controls available. They can go between your source(s) and the TU-8600 input. Generally not inexpensive. preamp Remote Volume Control - Placette Audio
Or, simply use a preamp with a remote.
Think that is something you will have to test. Perhaps Victor will have some insight. Tortuga & Luminous also offer high-end remote passives, as do a few others. Do wish Elekit offered the TU-8600 as a true amp (no volume control) rather than as an integrated amp. If you read the Stereophile review of the TU-8600 that may offer some insights into how Herb ran same and the volume settings.