I too have an Odyssey + and yes I have to run WMR then SteamVr (which loads Steam). I’ve not tried the alternative that @Gunnyhighway suggests. 
I only have a 1080 (NON Ti) card with 8gb VRAM.
I’m using tweaks from a video (around here recently I think) and getting 55-89. I almost hit 90 once or twice and it stays around 70 FPS in NTTR, though with simple missions. Without the tweaks it was about 45-55.
And yes there is a slight loss in graphical fidelity but, A) in the O+ I really don’t notice it; after almost 2 years now I’m ‘used to it’, and, B) the smoothness is like butta, baby.
Just simply flying around (NTTR and PG + Supercarrier) is a joy. Wish I could capture, for others on the fence concerning VR and Seat Shakers, the sense of immersion (there’s that word again) as I…cruise into the break, feeling the engines pitter-patter, roll hard (left of course) transmitting a slight shudder, then smoothly add on the G, feeling the rumble scale to my right hand, literally. I can tell my G-state to within +/- 1 G anymore.
Got it tweaked, finally, such that when you pull hard enough so that the AOA hits a certain point ('Vape’s coming of the wings for instance) it really starts to rattle. Think of those “WAKE UP” rumble strips alongside the roads for when you ‘wander’ out of your lane…whew, sorry, where was I :)…
Here’s the YT concerning the tweaks:
DCS VR Optimization (18.104.22.168)
 In fact I have seven apps running each time in DCS. It’s a process:
Those are in addition to WMR (again, SteamVR automagically runs Steam).
…turn on my seat shaker, position the HOTAS, pull all “remove before flight” pins…
I have 32Gb RAM. The Razer Cortex claims to give me back .5 to .9 GB prior to running, depending on what I’ve done before. Jury still out on this but it’s caused no issues so far.