What oils are you using? Some oils definitely feel greasier than others, regardless of amount used. However, I'm a 4a and I PS 99.7% of the time, so that doesn't bother me much.
It is super important that you listen to your hair's needs. You mentioned that twist-outs worked in the past, that could be because of the low manipulation involved. You may want to wear more low to no-manipulation styles if you're trying to grow. If you've been at the same length for 3 years, your retention is the issue, not growth itself. Try taking supremely good care of it and leaving it alone and see what happens.
I wish I would wear my hair out everyday! My hair would cause a flippin rebellion in here. I can't do that, RainyDays can and she's got gorgeous hair to prove it. I washed and conditioned my hair last week and let it air dry unstretched--my APL length hair was 3 inches long! I tried not trimming--umm, NO. My hair is NOT having it, so now I trim every 10 weeks. Oh, and I saw a friend of mine whom I hadn't seen in months, who didn't recognize me with my "short" haircut. Umm, dude, my hair is 4 inches longer than the last time I saw you... people see what they want to. Don't believe the hype!