Wife is 64 and about to turn 65. We are also getting lots of mail. I do not think it is IRV2. We will lose her coverage through her past employer and so will I so we both have to have supplemental coverage. Since, like you, we travel, an advantage plan will not work for us. I am leaning to AARP and Cigna for DW. Haven't picked a drug plan yet. Those that are against AARP seem to do so more for political reasons than cost reasons.
Luckily we will get the funds that the past employer had been paying in for us.
I suggest you find a broker that can guide you - most do not seem to get any difference in commission which ever insurance company you go with.
Perhaps in a few years the USA will have a single payer system and it will all be like medicare and it will not be so difficult.