Good update- sorry to hear about the colony failure. All-in-all it sounds like things are going well in your apiary and I like your idea of experimenting with a few side-by-side comparisons. I'll look forward to reading about your notes and conclusions.
Haven't done any feeding here yet but based on the amount of drawn comb in a few of the new swarm starts I may need to think long-and-hard about it...
Keep up the good work-