What's your batch size? Is 40lbs of base malt correct? Something doesn't seem to add up there for me. Also, while I think that GP isn't typical for the style, I have no problem with it per se.
If you enjoy making all those hop additions, go right ahead, but I think a 60 minute addition for all your IBU's (Cent is OK, I prefer CTZ or Chinook in this style), followed by a late-boil or flameout addition, and 1 dry hop addition at (or near) the end of fermentation is how I'd approach it. The steep and active fermentation dry hop that you have planned will probably lead to a hazy beer, leaning more towards a NEIPA. FYI, the hot steep will definitely add some IBU's (not a problem in this style, but something to keep in mind).
I don't keg-hop, so I can't help you on that one.