Nice. How are you handling the syncing? I wrote a really crappy SFTP program that syncs between my desktop and HTPC but that only really works in my house. Do you use Dropbox/etc?
Are you running newer versions of Kodi? I built a different setup for Linux years ago using Jarvis for it, but I'm sure it's changed a lot since. Did that Retroarch integration actually turn out to work well that they put in a few versions back?
Also, what do you use for inputs these days?
For the syncing, I installed a tool called SyncThing. For Windows there's an implementation, "SyncTrayzor," that lives in the systray and handles everything. Added a single directory (d:\emulation_saves) to it, putting everything in there. You can set up exclusions for it too, which is handy for Dolphin's stuff - syncing saves is great, syncing platform-specific settings is *not*, especially when some of those settings are geared towards a high-end graphics card on one device and towards Intel Iris on another. Not sure if SyncThing works outside the house, but honestly I don't really need it to work remotely. It can be kinda flaky with recognizing shares, but it usually works okay most of the time. Note that it's *just* saves I have syncing, not games or any other part of the setup.
I'm running Leia on at least a few of my devices, but honestly the setup hasn't changed appreciably since Gotham. Whoever develops Aeon Nox keeps pushing out new versions for each new version of Kodi and my setup just moves with it. (But I do have Kodi set up to make backups every evening, so if something does go wrong I can revert pretty easily.) There's even a Netflix plugin for newer Kodi versions.
Advanced Launcher is long dead unfortunately and it's a bit unwieldy to use - since it's so old none of the scrapers work anymore and adding anything to it is a heavily manual process - but I don't add things to it very often, and never in bulk. With AL you define file collections and the program that runs them, and it just submits a command-line request to the emulator. In my case it's *usually* retroarch - never played much with direct Kodi integration there - but Dolphin for GC/Wii, PCSX2 for PS2, etc. I might look into redoing it with one of the newer launchers (Advanced Emulator Launcher and Rom Collection Browser are the ones that currently seem to still be active) but I'm in no real hurry to head down that path. The submenu buttons link to AL paths, and I'm not sure I can do that with RCB or AEL.
Inputs are still the wireless 360 controllers with the transformable dpads. MS controllers Just Work with directinput and x-input, so there's very little fiddling that needs to happen to get them behaving correctly. I did add a few shortcuts using joy2key: clicking the right stick in (R3) calls a modifier. R3+dpad down minimizes, R3+dpad right does alt-tab, R3+dpad left does alt-shift-tab, and R3+L3 does alt-F4. There are a few custom J2K profiles that I've put together - PCSX2 terminates with esc, not alt-f4, and a handful of games actually bind things to R3+L3, but for the most part it works pretty well. I keep a wireless KBM setup around in the event I need to actually get into Windows to do something - this is the bit of the setup that I'm least happy with, but the need is fairly infrequent, thankfully.