Just team up yourself with someone +10
Then join a top tier guild, not that hard. Usually they require a pvp set that it's easily doable in 5x5.
I don't think you should think about pvp only from 1v1 circumstances.
I do think that a +2 should not win vs a +10, that means they balanced it, so amps should always matter and that it's a thing in all mmorpg games. Upgrades in general should matter.
Buffs aren't that expensive to buy.
About books, there aren't so many players that buy books and in EU server, legion side has way more books than elf side. They also give such a small advantage in big fights.
Atm, in pvp, no matter where (1v1, 2v2,5x5,gvg, etc) cc skills are winning you the fights. All are at least +8 since it's not that hard to get it, and all are using buffs since they are cheap.