It's a long and slippery slope it is! You will be amazed when you get your first negs, it's not just the sharpness (you will get that with your med.format) but the tonality which makes the difference.
I have used a few methods for processing, but always come back to the tray method. BTZS tubes are ok, and I have one of those Mod54 racks for the Pateson tanks. The Mod54 is a good idea but I occasionally find that the film will jump out and two sheets will stick together...not good! I still use it when I'm doing a quick job and just load with four sheets.
Once the tray method is mastered I can process 8 sheets at a time using 8x10 trays and a liter of chemistry.
Good luck with your 5x4, and all you need now are those extra lenses!