The base model Goldwing is $23,990, MSRP, plus freight, prep, taxes, yada yada yada. You're probably looking at $26+ OTD. Likely more.
$20k is a solid $4000 under MSRP. That easily pays for all that other stuff. What you need to do is consider if that's "going price" regionally, of that's really just a great deal to get you to buy. If it's "going price" in your area, then you need to see what you're getting along with that price. If that's Out The Door pricing, then jump on it. Great deal.
If they can't or won't do anything about the extra fees, then you need to compare that with other "going price" deals in your area. If they're all basically the same, then you have to compare back-end deals. Are you getting any scheduled maintenance, additions to the machine or your gear, are you getting free warranty bumps or road side assistance, do you have any particular affinity for the dealership in question, etc.
The bottom line is, most people would kill for $4k (or in this case, roughly 16%) off MSRP of any new bike deal.
Note: A popular discount bike retailer, Honda East of Toledo, only shows their MSRP numbers crossed out and a "Call for Quote" message on their site for all their in-stock wings. They have consistently been known to beat any advertised price, and cut substantial breaks for fees. Might be worth a call to them. I'm not affiliated, but I did save $1300 on a new CBR/F4i from them once. http://www.hondaeasttoledo.com