Any HGVC property bought on the resale market is a fantastic deal compared to buying directly from the developer. So yes, 5000 pts for $4K is a great deal. Congrats on the resale purchase!
In terms of resale prices, gold season at .80 / pt is not bad at all. Yes the same season/# of points can be found for less, or it can be bought at properties with less annual MF's. But I wouldn't sweat your deal at all, it's in the ballpark. Now enjoy your timeshare!