Based on your description of yourself, we are very close in size. I'm 5'11", 180. You are carrying almost twice the lead. In a full 2.5mil, I use 8# and am overweighted by at least 3# (on purpose). This is with the typical AL80 rental tank. 2# in each trim, 2# in each pocket. Been diving an AL i3 Dimension, also a back inflate. I think it's similar to the Zeagle except for the inflator system, but I've never used a Zeagle.
When I started, was having the same issue, and carrying almost as much (12#). Seemed like I had to fight a little at the surface. What I found was with less weight and counterintuitively, less air in the bc, it was a lot easier to relax and just float at the surface.
As others have suggested, play with tank positioning as well. As I dropped weight, had to play with the tank as well to adjust trim. Time in the water probably helps more than anything.
Now I am adjusting everything again-bought an AL Outlaw and a different pony....