MidiOut Thread events

I’m writing a sequencer (my first one).

anyway i need to send events from 64 parallel patterns running, so i need to send MidiOut messages from each pattern to different midi out devices (each pattern can have a different midi output device set).

anyway i was wondering what’s the best way to do so, should i call sendMessageNow() for each step at any moment of time, or use the background thread with sendBlockOfMessages (), witch of theese will give me better timing, and wont affect performacne as much.

i also noticed that the most of the CPU the app/plugin is using, is with paint() not with the actual midi processing, how can i improve the painting assuming all the led/buttons are png images. is buffering a good idea in this case ?