I cant see a shortage of ESL work in our lifetimes.

What is clear though, is you do need to do something as it appears you have no related qualifications at all. I assume you have a BA/BSc?

Three main things to consider IMO...

CELTA/Trinity > DELTA/Trinity Diploma.

Entry level qualification at CELTA/Trinity level, but this combined with a BA/BSc is probably enough to get you employed at entry lever higher at a heck of a lot of places. Add a DELTA or Trinity Diploma later and I would think you would be pretty well qualified and a desirable candidate in the private language schools and adult education sector, and eligible for senior positions.. This route is a vocational route I think...CELTA/DELTA is quite hands on, so its nothing if not practical. Initial certification is relatively affordable, find a good employer and DELTA sponsorship seems possible.

MA TESOL

Probably trumps the CELTA/Trinity route in many places, but not all. From reading ads, MA TESOL seems a 'must-have' for jobs in the Middle East. Obviously this is a more academic route and may/may not be as practical as the above certs. Anecdotal perhaps, but I have a recently graduated MA friend, who is happy to have completed her course, but doesnt think what she studied in the class as an MA student is especially relevant to what she has to do in the classroom as a teacher. Also could be expensive!

Qualified Teacher Status (in UK), State certified teaching etc.

Rarely offered with an ESL/EFL certification in the UK. This may differ in your neck of the woods though. Obviously a 'must-have' if you want to teach subjects in state schools at home, or International schools abroad. This is a clear break from ESL/EFL though, and may well mean following a different path to the one you are currently on.

If you want to stay in ESL/EFL, this is unlikely to help you get the plum jobs in many places with switched on employers IMO. Its no secret that teaching subjects in L1 is a very different job to teaching L2 using L2 as mode of instruction. Its also no secret that many state certified teachers know bugger all about teaching EFL!

Great package if you work in the UK state system though! But you have mentioned the USA right? Apparently lots of teachers there are finding it hard to get work, so I guess its not the best time at the moment!

As I see it ... thats the three routes to look at, all have different benefits ... and all have different costs. One thing is for sure, the longer you leave it, the further you will fall behind, some employers may not even recognise your current experience at all, as its pre-certification experience. Its a common requirement and many job adverts state experience required POST certification.

All of this is based on my research at looking at improving my qualfications and prospects. I am NOT an expert, but have been considering the same options.