If it's just for you, then ignore "styles" but if it's great, there's always Specialty categories if you enter comps.
Looking at the Tinseth IBUs, I would expect this to end up tasting sweetish, if only for the other ingredients helping to beat down the hops.
Approx. 2.5 oz of those Centennial hops would reach 76 IBU and get the BU:GU ratio up to 75%, which looks better than the current 40%.
If you have a higher AA% hop for some clean bittering that may reduce the boiling of so much vegetal matter for that long.
The coffee would add more roasted flavors and perhaps more dryness, but may leave it sweet and dry, rather than balanced or even bitter/hoppy, which most expect in stouts. Again, it's for you, first and foremost, so it's up to you. I know a sweet mead guy locally that can't stand IBU's over 15 or so. Face scrunches up like a lemon.