You're losing crucial time for scouting and decision making. Which is simply better for players who will play according to their 1 scenario and worse for players who want to be creative and adjust their plans. I'm all up for DWL on say Islands or TI where the game plan is quite straight forward. Can see it on Arabia and open maps. But against mixing it to maps heavily about decision making or scouting, such as Arena, MR, etc.
I have always been able to spot the 5 relics then come back to lure deers everytime I played arena in DWL. What else do you need to find with your scout? You can't see how many vils on stone/gold your opponent has. And you can spot a trush by checking if his score drops 50 points. If it takes 12 minutes to decide your plan then the problem is not a 9 vils start.