Maco antenna tuned for ten meters about 228" +/- or about 19 feet. Mast at least tower 3' or 5' + 3' for 2 meter beam if mounted to the mast plus separation space between 2m and 10 meter antenna above tripod and below 10m antenna.19" each for another 3 feet. now you are about 10 to 11 feet plus the 19 feet of antenna. go with the 5 foot tripod securely mounted to the roof. that's about 29 ' x wind load area. I have not done something like that since the late 70's but it will work. follow tower manufactures mounting advice. Be safe.
Yes, that is quite a bit of mass up on the roof, it only takes one leg to tear out on a tripod tower and it is game over.
Definitely re-enforce in the attic first and even consider mounting galvanized steel 90 degree angle to the outside of the roof (to get more places to spread out that load. Look at the joists in the attic at the crown, sometimes they are using nothing more than particle board for roof sheeting and not something like 3/4" marine grade plywood. I have been surprised as I designed, spec'ed out and oversaw the construction of my house. The day I came home from work and inspected I saw they were trying to install this really cheap particle board type stuff and had a big argument with the builder who had to take that stuff back and put up what was on the specs they signed the contract for.
There are four legged tower roof kits (quadpods? <lol> Glen Martin roof mounts). I would be nervous about having that much of a three legged "crowbar" mounted on my roof. Sooner or later it would tear free and I would be looking at skylight kits to fill up this gigantic hole. (or a submarine conning tower on top of the house).