Yeah, that looks like it will work. I would worry on rock face. There the whole tip will bite, release and bite, sorta. As it rolls from one side it will go flat, reducing the grip all the way around, the main reason they have a pointed tip. This is the reason I insert a plug with a 1/8-3/32″ stove bolt screwed through it extending down about a 1/2-1″. It acts like a regular carbide tip, cept it is steel and wears quicker. I am afraid the aluminum will wear relatively fast, also. Anyway, on wood it will also slip a bit. Again, without some point to dig in, there will always be a chance of slippage.
It should work for now. Yeah carbon stuff can be a bit difficult because of cost and time. I have several old broken fishing rods that often supply ne with odd sized tubing. No, the pole itself doesn’t need to be tapered or only slightly. I think I have made about a dozen or so and given them away to people to use. The whole pole costs less than $15 even at todays prices, and only weigh about 4oz/44″. (A 10′ Panfish pole works pretty well.)
I have had trouble with a lot of different tips. They all taper pretty wide at the top. I was always catching them on something, especially between rocks where the pivot pressure can shear the tip right off. After about 10 years and 4-5 pair, I just started making my own. They actually work a LOT better, but, they are not collapsible.
They don’t have handles, but have rubber wrist strap mounts, and tip mounts, soo, they are even shock resistant.
Anyway, yours seem like they will work.