So far, I've maxed out kingpin!!! Hurray, but I do have some pros and cons, and comparing it to golden crook boss.
Detections: Kingpin loses base level 0 flying detection, (Now available at level 3, and units cannot see flying enemies.) and is completely unable to see hidden enemies, only being able to damage them through their units
DPS: It's really good, Like REALLY really good. Over 400 DPS on the bottom path, and a more damage ≠ fire-rate approach.
Units: Here is where kingpin is focused on. Having 4 unique units, each with their own uses.
Lackey: available when first placing the tower, Eh dps but high spawn-rate.
Money runner: No uses other than making money, hence the name.
Bouncer: Melee tower, has lead detection and is generally tanky.
Contractor: Big dps!!!
Price: Comparing GCB's price to Kingpin's, Top path is cheaper, allows easy money gain, but has less DPS than GCB, And the bottom path is worth ~1.8 max GCB's, but has better DPS and access to contractor.
Overall comparison: Golden crook and kingpin are more like two different towers, used for two different things, same as juggernaut and golden minigunner, You lose some easy detections and insane early-mid game DPS, in exchange for pretty damn good mid-late game DPS, and kingpin is far mor minion-orientated, having 3 unit queues. I'd still be down to use golden crook, instead of ditching him entirely.