I will toss in some additional thoughts as you weigh your options

. You mentioned yeast harvesting. I don't ship liquid yeasts in the summer if it can be helped. Obviously you are very aware of your shipping challenges and transit times. I've worked in warehouses in the summer and they can get hot and the trailers get real hot! Personally I am less concerned about shipping liquid yeasts during cooler periods. I bank yeasts by overbuilding starters and storing samples in bottles. One can also go so far as to store yeasts on slants. Building the starters does require periodic DME purchases too, also a shipping concern for you. Note here that you could also build starters for your dry yeast by dividing a packet. A packet good enough for 5 gallons could by divided ~10x to make 10 two liter starters. Making starters is easiest in metric, 10 ml H2O to 1 gram DME. A two liter starter needs 200g, so 10x200g=2000g=2kg DME per packet. A 3lb package of DME=1.36kg, which would be almost 7 starters. Three pounds is the size I generally buy. Harvesting yeast from the fermenter is free. Since I don't do this much, I am less familiar with storage issues but it seems people have longer term storage concerns. But you would need to factor in your shipping specifics to get a better economic assessment.
Checking out further your Fermtank Pro possibility. It has plenty of ports, the leg architecture would not interfere with an elbow as my X2 does, and the TC clamps have thin width on the thumbscrews. On a 7-8 gallon conical, multiple ports on the cone get crowded. Another plus to the Pro here as the cone ports are well spaced. Not well-spaced on my X2. Cons are the two valves. The butterfly valve in the bottom is not a trigger squeeze and will have just a few positions. It's not critical there but in my experience, the ball handle butterfly valves may not be as nicely made. My Brewbuilt 2" squeeze trigger is my favorite squeeze trigger as it has a short handle and seems well built. (But I can't use it on my 1.5" racking arm where I really need a short trigger and Brewbuilt doesn't seem to offer a 1.5" squeeze trigger.) The valve on the racking arm for the Pro is a ball valve. Since flow is through the pickup arm, the port is already constricted but the ball valve is a little less sanitary. They are cutting the corner a little on price as some manufacturers put a butterfly valve there. It's also barbed and the barb may or may not come off. The valve could be repurposed to the blowoff tube where it is useful to close off that port for spunding or pressure transfer. I have a couple of TC inline ball valves I picked up used and use them that way. My SSBT uni has a mounted blow off tube standard. The Pro at 32 5/8" is also taller than a 5 gallon ball lock, and has a wider base. If it could fit in a mini-fridge, it would be a big one quite possibly needing a collar and no freezer section or you could move the freezer. Finding something used could be challenging.