Instead of straightening, why don't you try twist outs or braid outs for more "wavy" looking hair? Honestly, I would kill to have 3b hair.
2c-3a - coarse - normal-high porosity - high density - growing out to donate

NP/LP: , CJ Daily Fix, KMF Whenever Cond./ Giovanni TTTT
RO/LI: CJ Argan & Olive Oil, KCKT, YTCucs
DT: Coconut Oil + scalp massage
OIL/STYLER: SM Elixir / KCCC, SS CEJ
COLOR: henna, amla & indigo