Dumb question about leveling

Ok -- so here's my dumb question about rig leveling: right now, the front end of my 3124kb tilts up a wee bit, on account of my current WD shank (hitchbar) not having sufficient drop. I did make sure that when adjusting the chains, etc. that the front end of my Expedition came down to where it was, eliminating any lift caused by the tongue.

How critical is it to get things perfectly level? I ask because it looks like I'd need to buy another hitchbar with more drop if I want things to be picture perfect.

I'd post a pic of it hitched up but everything's popped up right now whilst I wait for the seal kit for my toilet (blasted flange was leaking -- figured I might as well seal everything while I have it apart).

Thanks!
John