Oh boy, you certainly have a few dilemmas going on here. At least you've given yourself the options and you just have to select one.
You should eliminate #4. You need to have a second cat with the energy to keep up with a bengal. This should be another bengal. A savannah will grow to double the size of your bengal -- and if that savannah is a male, there could be huge territorial and aggression issues. I'm not sure the Servials and ALCs get along in the wild. If you were to go the savannah route, please get an F4 or higher! An EG savannah with an SBT bengal might be a problem.
The main thing to decide is to whether to let Snickers have a litter of kittens. Every breeder tries to ensure their kittens go to great homes. But, I read on Facebook from all the breeders I follow, "something happened and Ebony has been returned to us and has to be re-homed." I'm sure out of 100 kittens, maybe one gets returned.
The other thing is that Snickers is either your pet or she's a breeding queen. There is a difference. You can let her have one litter and see how things go. Then she can be spayed. Once spayed, you can't reverse it to have kittens.
That still leaves the issue of a stud. Once you get one, you are pretty much in the business of breeding. You don't buy a stud for one litter. And I will say that with many breeders, the studs go back and forth and all around the world. You don't want to get attached to a stud and if he is spraying all over mankind, you probably then don't really mind. Would Snicker's breeder have a stud (not Snicker's dad) that she could be mated with?
Snickers is young and still has some time. Most females are bred after their first heat (so the yowling can be annoying). And after a female has kittens, she can go into heat again before they are completely weaned -- more yowling for a male. If you are up for this and are prepared to deal with this ... and you want a bengal family of kittens running around where you can keep a kitten and get Snickers fixed, then do it! There is no law against this. I do think another bengal would be best for Snickers and not a Savannah or Toyger or any other breed. It somehow sounds as if you want to have a home filled with exotic animals, which is fine ... if you have the room and the heart for them all.