I'm assuming there will be less arrests, does that mean crime rates will go up? More cases will go unsolved?
With half of the DEA now focused on immigration, will that result in a flood of drugs coming into the US and a drop in prices?
No agency tasked with alarm-based enforcement (ex: War on *) will ever silence the alarm. After the need (actual or otherwise) is passed, numbers are massaged and the original mandate is redefined into an expanded scope.
That's how it's been with past, more constitutional administrations. What we've seen recently is that national threats are crafted so that enemies of the admin are targeted.
For any excess capacity of force that ICE may have, that's where I expect to see it directed.