No, auto-granted AAs can be gotten by anyone while on All-access. So just have to subscribe for a month.
I suggest spending 15 minutes doing Teek 85/90/90 alternate to grab about 190AA before you use auto-grant.

Do this at around level 100 when you can actually find some ROF/COTF AAs to spend that 90AA (100 AAs can be kept in reserve).
Heroics are useful for a few things: mount, auto-granted DON and MPG AAs which you do not get with a regular character unless you actually do the quests, not hard but takes a bit of time.
The most important thing heroics get are the heroic augment quests in HOT and Feerrott. The augments are non-prestige and decent for tanks so makes it easy to fill up all slots.
The hard part is still PL 51-75, finding a pleasant zone to PL is not that easy. Some people swear by that POK instance but I do not like it because I get lost in it and waste time.