Person 1 is the kind of gal I think of as perfect for a younger retiree - something late teens that may be a little too stiff nowadays to show or jump around much, but with miles and that deserves to be spoiled. Breed not a big deal, but for plus sized and older, I would vote small and wide - short-backed small QH/ paint, or Morgan or Appy (if they have manners), or draft or Haflinger X (if they're not inclined to be pushy). Gaited breeds known for being kind, especially TWH, maybe?

Person 2... My first thought is Appendix or TB x ... maybe a lighter draft x. Options are more wide open though; any solid citizen from any reasonably athletic breed - my TB is super mellow, Appies, QHs, paints, etc.