A large sized ancestry would also be the only character who would have to pay a premium for gear now that Small and Medium gear is standardized.
Not a huge issue since Giant Totem barbarians already have to deal with buying larger weapons, and the rules for doing so exist. But it may be a pain outfitting a lvl 1 large sized character depending on armor and weapon choice.
"Standing upright" large characters would have more reach, which is pretty nice, especially if you have AoOs of some kind. Could be an action advantage because enemies will need more than one Step to get away from you.
But I've seen constantly-big PCs also get a lot of punishment. A lot of the commonly used flipmats have 5ft corridors and doors. And quite often, enemies do tend to focus on the big guy, so you tend to get hit more.