Oh yeah, I never use the step sequencer, so cannot help you there. When I want a step sequencer I just lock my notes to nearest line on the piano roll and zoom in until I have 16ths.
For MIDI, I think that’s a lot better than you’re thinking, it’s just not super obvious. I use the dedicated midi out plugin (it loads as an instrument) whenever I want to send midi not directly to one instrument. Make sure it has an output port set, even 0 will work. Then load up the plugin you want and go to the wrapper settings and look for the port #. It will default to none, but set that to the same number as the midi out and you’re in business. I don’t use it for very advanced stuff, just ghost kicks and the occasional tuned FX, but I’ve never had it not work.
I actually never learned patcher, if I’m using that many FX, you can route any mixer buss to any other mixer bus with the green wires at the bottom of the mixer channel. Just un-route it from the master and send it to another mixer channel. Protip, you can have unlimited send FX this way if you use the FX full wet and leave the other channel’s connection to the master alone. Just leave any subsequent channels at unity gain or it will mess up the levels you set in the mixer.
I think FL is very cautious about pointing multiple modulators/automations at a single destination. IDK why, I cannot recall it ever giving me a problem, but I just uncheck the “remove conflicts” box in the controller mapper and you’re set. And you should be fine with the default input=output formula most of the time. I use this all the time to point one automation clip at multiple filters for example - I bus my drums together, but send them to reverb individually, so I have to filter all the drum sounds individually or when I close the filter my drum reverbs come through at full range and it sounds weird. So I do one automation control for the frequency of the snare and put the same filter on all my other drum sounds and run them all off that one snare automation.