Agreed. Unless you are going to use juice concentrates and not fresh fruit, the conical fermenter will be a royal pain. I personally use 3 gallon carboys because of the weight and my wine consumption rate. Edit (Correction/clarification Carboys for aging, 5 gallon bucket for fermenting.) At 72 the idea of moving or dealing with 5-6 gallon carboy is a non-starter. If I wanted larger batches I could (and have) used multiple carboys. One other point is that all but 4 of my "1 Gal" carboys are actually 4 liter carboys because they are recycling center sourced and Carlo Rossi containers are 4 liter not 1 gallon. That means that when I bottle I will always have at least one good glass of wine left to enjoy on bottling day.
Sounds like you have a working plan and moving up to 3 gallon carboys should work nicely for you. (Also if you can find a 1/8 tsp measuring spoon, that's the amount of K-meta for a 3 gallon batch of wine during your aging racking.