I, too, had trouble with unevenness when I tried minimal agitation in trays.
I use a method similar to Sandy's. I use paint buckets from the hardware store to hold my open-ended PVC tubes. One for prewash and one for developer. I reuse the prewash bucket for stop. Of course, this must be done in the dark, but that poses no problem for me. A five gallon bucket will hold 5 8x10 tubes, and would hold six if I could find the thinner walled PVC. I use a 1 1/2 gallon bucket for 4x5 and 2x3. That bucket will hold 8 tubes.
I'll also comment on an earlier post in this thread about avoiding temperature shock. My negatives have improved greatly since I gave in to the high temperatures here in Florida, and I began to use development methods based on the temperature of my wash water. In the summer, I can't get it lower than 80F, so I worked out developing times at 80F. My winter times, when wash water drops to 74F, are longer. This has been working very well for me.