What do you mean hybrid system? Were you thinking about using RO/DI for the whole house??
RO water is certainly safe to drink but it lacks minerals that you need, so it's not a good idea to only drink that. The only time I've been drinking it was when there were problem with the quality of the city's tap water.
I used to have a reef so I still have a RO/DI unit. It goes only to the aquarium, with an auto-topoff system and a switch that allows me to fill bottles for water changes.
I'm currently changing my 95g from reef to planted freshwater. I will still need mostly demineralized water as top-off for my 25g. But my 95g will have automated water changes, and I dont feel I need RO/DI water for it, I only need to remove chlorine from tap water.
So here is how I plan to setup my RO/DI.
RO/DI units have 4 stages (some have 5, then one of the stages is there twice). The water goes through filters in that order : sediment, carbon, membrane, DI.
I will first change it to : sediment, carbon, sediment. The reason I use a second sediment is to keep carbon fines from getting into the aquarium, since they seem to be the cause of HLLE disease. It may not be necessary, but I prefer to be on the safe side.
After this second sediment filter there will be a T with a solenoid valve on each side.
The solenoid on one side is controled by the auto-topoff float switch and the water goes straight to the aquarium.
The solenoid on the other side is controled by the bottle filling system (on/off switch + float switch, so the water only flows when this system is on and the bottle is not full). The water goes through the RO membrane (then DI filter but I don't think it will be needed) then to the bottle-filling hose.