Hmm, maybe ReVancedExtended would solve your problems? I know my RvM has no issues with custom patches even without root, but it might just be a device/os version weirdness. I’ve heard RvX is overall better with the non-root support, but I’ve never used it personally
There also are a lot of tourists coming to the Christmas markets, sometimes from quite far away.
Those people either completely take public transit (they’ll be drinking anyways, so public transit is easier to get back home) or go for the park + ride offers that pop up during that time. It works pretty well.