I'm trying to tackle this end of m4l currently aswell. My test patch was just 8 itables. Depending on how fast I scanned them I was able to get abletons UI to slow down:) So I was assuming I needed to learn some process prioritising and use of speedlim, but it seems more related to limits in updating visual components? An itable preset isn't exactly processor intensive code, but I would get slow preset loads and some crashes on mouseover from itable's value pop-up I believe.

A never ending progression of almost doing exactly what you want, thus is life my friend.

I've been getting a similar problem when trying to load roughly 300 umenu settings with time-sensitive bangs to "get parameter" messages - I've tried clientwindow prioritization and greedy, but I'm at a total loss for how to continue.

Try lowering the update limit of each parameter to 30 ms (default 1 ms which is way too fast) and also adding a speedlim (30) to other objects to reduce the amount of data that has to be processed.