FWIW, if going for the API, why not get a second hand API? That way, the resale value will allow you to trade in without loss if you change your mind. If Neve-style would be more to your taste, the DIY version of the Sound Skulptor MP573 isn't bad value; nor is the Audio Maintenance one, which includes both pre and EQ in a 2U module.
Also, they're not out just yet, but Lindell Audio are releasing three modules for $299 each — a mic pre, an EQ and a compressor. If they're anything like as good sounding as the 17x compressor reviewed last month then they should be a bit of a bargain.