Sanderxpander
An EQ is still an EQ, barring any "vintage modeling". I like some third party plugs I have (FabFilter, Waves and some others) but if you know the basic controls you can get by with most DAWs. A delay will still have a feedback and a mix control, an EQ has Q, frequency and gain and a compressor has a threshold and a ratio.

While that is technically true, it's a bit of an oversimplification. Their are some plugins which combine types of processing like EQ and Compression to create a certain "sound" that is difficult to recreate for the laymen like us. There is one in particular (I cannot remember the name) that makes a huge difference to the overall sound of the mix. I have no doubt that certain engineers can recreate that using built in plugins but we are not them. I am a songwriter and not an engineer. I do not, nor do I care to, become that much of an expert when a 3rd party plugin can do it for me. 
 
Cheers everyone! Thanks for the feedback!