in terms of recording to the sequencer, you’ll be fine with hooking up a midi keyboard and jamming away. i sketch & record monophonic lines this way all this time.
tbh though, it took me awhile to get used to the mnm so i could work that way, mostly because of my own tastes. i had the typical new-user experience of thinking the mnm sounded really thin straight out of the box, and many of its strengths only started appearing once i started exploring its routing possibilities – chaining up effects, using the bus system, that sort of thing. only after i made that a part of my workflow was i able to get what i considered to be lush sounds out of a monophonic voice.
poly lines are trickier for me because they unfortunately preclude you from using the bus system at the same time. if that ends up being important to you, you’ll need to go back and program each voice of your sketch as a mono line.
a buddy once told me that the mono is a programmer’s synth. he’s largely right imho. you’ll be fine with basic note entry using your keyboard, but sequencer interaction is where it really starts to shine. you probably know that about elektron gear by now however 
