My first job?
If you only intend to instruct just to build hours, then I would suggest you tow gliders or drop parachutists.
I have been flying now for 40 years and am still going strong...eighteen months left on my licence. I started as an instructor and put all my efforts into becoming a good instructor. In the meantime I studied by correspondence for the CPL/IR.
I eventually landed an airline job after insructing for 3 years. My instructing experience and my enjoyment of it stood me in good stead in later years when I became a Line Trainer, Sim. instructor, then TRE/IRE, Check & Training Captain on various aircraft. I think instructing gives you a lot of experience and makes you more employable as an airline co-pilot if there is a choice between two candidates, one of whom hasn't been an instrucor. So, I would say go for it, but not half-heartedly.