Are the VIP and the RIP tours something you buy in addition to your event ticket, or is entry included in the price of the tour?
In addition to event ticket. Think of it this way:
Park ticket gets you into the park (this will be important if you want to take advantage of Stay and Scream)
HHN ticket gets you into the nighttime event (or keeps you in the park if you go with Stay and Scream)
HHN Express ticket grants you access to the house express lines
HHN RIP ticket puts you in a tour group for the night
Recommendations:
If you have a daytime ticket and HHN ticket, take advantage of Stay and Scream and stay in the park at closing time.
If you have a daytime ticket and HHN + Express pass, also take advantage of Stay and Scream at closing time.
If you have HHN ticket only, be outside the gate very early to get in line to enter for HHN.
If you have HHN + Express only, also get in line outside the gate early to get in.
If you have HHN + RIP tour ticket, you can be there early (if you have daytime ticket) or use the RIP entrance before your tour starts (1 hour before I think?)
As for the daytime Unmasking the Horror tours, I don't think you need a daytime ticket. We've only done it once, and we entered and exited via the Blue Man Group building.
Hope this makes sense, but let me know if I need to clarify.