I was planning on doing something similar, maybe even upgrade the PSU of the 210 as well. But I expected the 218 to take over the volume of the speakerlink input. Now I would loose my Roon embedded volume control when using the 210 as Roon endpoint. I guess I have to accept that.
PS: I am impressed by the SQ of the 210, I should upgrade the PSU just to compare with my 218, it might be better.

Main: DSP8000SE< 218 < Farad Super3 TMCB < PS Audio P10. Room correction: Focus Fidelity.
Second: Fostex Fe206NV2 < Audio innovations 500 valve amp < Wiim Pro +
Study: DSP33 < Reviver < MS200
Server: ROCK + Tidal on NUC, fiber on 2x cisco 2960, HD-Plex LPS.
Gone: DSP7200SEu, DSW, DSP5500mkI & DSP5000mkI, 508.20, 210