I currently have no layers and I have 2b armpit length hair. I think it works well for me. Since my hair is very fine and medium density, I dont have to worry about too much volume or triangle head syndrome. I have the opposite problem, I dont want my hair to look too thin at the very bottom layers because that has happened to me before and the only option is to grow it out and keep cutting off layers to get it all one length again and i'm trying to get mine to BSL/waist length for my wedding next summer. Still, I keep going back and fourth about cutting layers into mine since so many here have had success with them.

A lot of wavies seem to find that their waves spring up more with layers instead of having a lot of wave on the bottom and not much on top (triangle head) or the weight of the hair stretching out the waves, especially at longer lengths.

Another option if you're concerned about too much volume, you could always have your hairstylist reshape your current cut as well. Many curly stylists are familiar with the volume problems of curly hair and can make it lay closer to how you want it. That way, you wouldn't have to wait for it to all get to one length to see if al one length even works how you want it to.
~Curly, Runner, Self-confessed Nerd~

2a no product/2b-c styled
Low Porosity, Fine
No poo-SM
Co wash-VO5 kiwi lime*
Rinse out- ION EC
Leave in - Giovanni Direct then SM smoothie (ends only)
Stylers-SM souffle topped with BRHG*

Hair hates: glycerin (high dews here in TX)
Hair likes: Coconut Oil*, protein