I love Durst enlargers, but that LPL you have is pretty nice. Have you looked into the condenser head for the LPL? That will certainly bring your times down.

Another thing to consider is to get a 4x5 enlarger with a 200W or 250W bulb. Then use a 6x7 mixing box. That should get you brighter than a 6x7 enlarger with a 150 or 100w bulb.