What does the guy that did the work say; has he driven it? He should know if it is not driving or steering correctly. Ride with him when he drives it to see if you detect the skating so you can point it out.
Other suggestions: 1. Check the tires. One way is to rotate them. If you have a bad tire the driving characteristics should change as the bad tire is moved to another location. 2. Has the steering box been checked for looseness or other wear. 3. Were the control arm bushings checked. 4. Check wheel bearings for looseness.
I agree with all of this, and if you can get them the final settings of the alignment.
When you describe the front end "skating" I think of it sliding, only to a lesser degree, as it would on ice when turn the steering wheel. You basically turn but it goes straight for a while?
If that is the case it would indicate understeer from the van which is the way most of them are because of the heavy rear weight. You will also need larger than you might like correction from the steering wheel of maybe an inch or two of turn to correct an offline from gust of wind.
If this is the case, improvements can be made to make it better. In general the things that will reduce understeer would be:
Increased front tire pressure (did you ever check to try the 65 front, 80 rear that was recommeded)
Stiffer rear springs and higher damping shocks (or just getting better shocks all the way around is most common)
Adding a rear sway bar
Possibly better tires
Possibly better alignment settings
Possibly a wheel change if you have the aluminum wheels
Understeer is an odd handling that is defined as the front tires having less traction than the rear so the vehicle does turn as much as it should because the front tires are slipping some (skating?).
It is also a thing that has a very wide range of how drivers think about it. Some drivers, like me, want as little understeer as is possible while others think that a vehicle with very low understeer is "twitchy" and hard to drive (think sports car). They prefer the more lazy, slower responding, steering which requires larger steering inputs (think 1970s Cadillac). Personal observation is that folks that like having some understeer would be the ones with the 10 and 2 very firm grip on wheel (big inputs kind of natural in that position, I think) while the one light hand on wheel folks or two lightly on the bottom like less understeer as big inputs aren't as easy to do from those positions.
Bottom line is what the driver prefers determines what the best setup is for handling.
A decent indicator of how much understeer you are seeing would be how far you need to correct normal offline events at freeway speed. When you start to get to much over an 1-1.5" it generally would seem to be getting too high for many people.
