When you're leveling, just Respec to whatever the group needs. Aug: celerity (for melee groups), Pac: pom and AOE stun (for bomb groups). For rvr, personal preference. Do you want to be offensive support or defensive support? Pac has a lot to do and is more offensively driven, controlling and interrupting the enemy. Aug is more defensive and normally the main healing source.
Aug: 36 Aug, 40 mend (for faster cure nearsight) Pac: 36 PAC, 40 mend Tri spec Pac: 38 PAC, 33 mend, 19 Aug (what I run so I have green celerity in pve groups with no Aug heal and you can small man decently.. biggest downside is 6s cure nearsight