I recreated my very first character -- a human warrior, because in the last-push alpha test I joined in 2004, there was no Horde -- and logged in. Immediately, I was surprised by how good the graphics actually looked, for being 15 year old textures-on-polygons. Warcraft's bright colors and cartoony aesthetic continue to this day, so all the increased resolution and better-contoured characters in Lordaeron don't really change the game's visual aesthetic.
Thanks so much for the replies. I think I am somewhat of a collector/roster builder. I go around doing the dailies but I also like buying pets just for their looks. I watched hazelnutty on youtube last night. I think I will focus on doing the expeditions when I have time to get all the pets that come from that. Then I will go back and do old raids like Eekwibble suggested.