Sequence MD with OT! 
Many tips here :
http://tarekith.com/assets/machinedrum_tipsandtricks.htm
I’d say try to layer sounds (RELATE > TRIG POS), use lfos on CTR AL machine, sequence MD machines with it’s midi tracks with random lfo on notes (midi loopback)… buy a UW…
I completely agree with this.
no
Who knows, it depends which is more useful to you. I had one of those green KAOS pads, which i never thought i would be able to get rid of, so i gave it away. Looking back it kind of could do some cool stuff with midi looping but it was so limited in the controller aspect. But IMO Akai mini controllers suck almost equally so idk. Try to trade for some other korg gear with midi! 
It’s the only Elekton box of the old set I do not have. I have seen Octos quite cheap ($1100au) but I am yet to pick one up. My introduction to modular has put a stop to any outboard gear purchases. One day I will grab one.
Cheers for the tips.
Get back to the raw sounds of the MD. Like the basic GND Machines. Get the manual out and get to know the MD’s Machines, how they work and what they can do for you. Samples work great but not as well as the Machines in the MD. Try using multiple LFO’s on a single channel. Use lower setting for movement.
Don’t try to overdo it with the MD. It’s simplicity is where the beauty lies. Like holding the Function button and changing all channels with any setting that can be altered by a Data Entry Knob.
I would use the Digitakt for samples. You can also control the Digitakt with the MD MID machines as well.
The MD is a machine that rewards you when you dive into the manual and learn what is inside.
Don’t give up on the Machinedrum! It’s an excellent piece of gear. It rewards patience and experimentation. Try and tweak the Dynamix Compressor, it has a significant effect on the overall sound. Especially with the way individual sounds interact when playing simultaneously. Also clever use of the LFOs can help change sounds or add movement.