I'm not making any judgements on you, but in my experience "not out-of-the-world pay, and move them up fast if they prove their worth" usually turns into "cannot afford significant/any increases/bonuses due to market conditions/losing major clients/my new boat".

Unless it's in writing, promises of large future adjustments are not really worth relying on. At best you might actually get what was promised, or you will end up feeling ripped off and mislead.