'703
I can't speak for others but having hired quite a few pilots over the years including first jobs this is my 2 cents worth:
First is attitude... you would be surprised how many people think I owe them a job.
Second is experience appropriate to the role... for example it pays to learn what the employer wants, with minimum hours etc, before you apply. If they require turbine time for example and you only have a CPL with a basic piston MECIR don't waste their time applying unless you are applying for some other role (say ops or ground handling) that might get you a leg up later on.
Third is hours. The RA hours are fine, but 1,000 hours RA instruction compared to 1,000 hours multi IFR charter are not in the same league.
Fourth return of service. If I hire someone I don''t want them piss off just after I get them trained endorsed etc
Fifth is persistence. It is a tough industry and weeds out the weak.
As for RA vs 172. Think about where do you want to be in 5 years and 10 years time, and take or create the opportunities that will get you there.
Personally I would not view much difference between 100 hours RA versus 172 on your CV, you need to consider which will give you the best experience and is most likely to open up opportunities... if it is paid job in either go for it!