Thanks, PhilP, but also TNX Paul M for your wondering was mine until PhilP cut.
Right then, the MRC gets light duty (the Stainz with a shorty train or Fiery Elias, the steam tramway with two light coaches and the 0-6-2 needs something like the MRC9900 (5.5Amps I learned from MRC) or MRC9950 7.5Amps). Of course, I'm open to other suggestions DIY inclusive (but it's decades ago that I cobbled a we controller together for Z scale equipment with circuitry to up the flow where contact got poor, nothing fancy).
Oh, and this wrt to top speed ...Zillertalbahn back in the days of steam with the U43 types about 35 km/h, somewhat faster with a former Bosnian narrow gauge 2-8-0, and Retian Railway steam 45 km/h, electric 55 km/h and post-WW II things picked up. I believe allowed V max is 90 km/h which is possible on some stretches from Chur to Thusis and somewhat less (?) to Ilanz (Surselva) or Schiers (Prättigau). Scale it all (at 22.5) and top speed is less than 2ft per second. Perfect to watch the rods 'knit' away ;-)
A gentleman, a scholar, and a railway modeller....
TNX, Gizzy. I'll need advice in many an aspect. Just became fully clear to me that my power packs won't do (MRC 1300, 1370) and wondering what people think about their big ThrottlePack 9950. Fine for DC (switch for big scales/smaller scales) and 'future proof' as it works for DCC as well. I don't think I will delve into that Real Soon Now but battery power and radio control might become the way to go once I extend the layout from beneath the cover of the deck.
Meanwhile I acquired a Tech3 PowerCommand output 20VDC (variable, momentum & brake), 19VAC fixed, 20VDC fixed. And the firstr snow is here. I move the layout from under deck onto the floor in a downstairs area to keep on trying and testing (common rail and more). Things remain analog. Eventually when enlarging layout outdoors I might consider a locomotive with onboard power and radio control.