Congrats! Sounds like you're on your way. A few thoughts:

I start with 50M+50Y if I have no other reference point. Everything I print gets logged to a spreadsheet, and I'm starting to build up a pretty good database. This means I can filter by film type and other values consistent with what I plan to print, and calculate a more targeted starting filtration as needed.

My experience is that the smell of blix gets worse as it becomes exhausted -- more like ammonia. I use the Unicolor drums with motor base and have no desire to go to trays. Just because you can tolerate the smell doesn't mean you should. At least make sure you're in a well-ventilated area.

Even so, I think trays work best with room temperature processing. If you intend to continue developing at 104F, I think you're going to have a hard time maintaining that in open trays. Results could be inconsistent. Also, I've moved from two-bath to four-bath processing (dev/stop/rinse/blix).

Whether you're using a motor base or agitating the drums manually, make sure you're working on a completely level surface. 60ml in an 8x10 Unicolor drum should work fine.

As far as focusing, you should be able to see grain. Open the lens wide, use white light, and find a highlight area to focus. Of course, I print a lot of Portra and Superia 400. I would expect Ektar to have finer grain.

Good luck!