Melanistic, snow, marble, blue, are all recessive traits, they can all be carried by cats unknowingly.
Melanistic, snow and blue can be DNA tested for but marble cannot.
In order to use a cat that is melanistic, blue, snow or marble and introduce it into a brown program then you should be aware that you will produce kittens that are all carriers for the trait.
That is fine if for instance your intention is to have a snow marble program, you breed your non-carrying browns to a snow marble, all kittens are then snow marble carriers and bred to a snow marble will give you half snow kittens, you choose the snow marbles and breed again to a snow marble and you then have a snow marble program. The unwanted brown cats (carriers) you can pet off or sell to another snow or marble program.
Where it gets complicated is when the cats show an "undesirable" trait ie melanistic or blue. By breeding with those cats, the progeny will all be carriers and that is fine if you are going to neuter them all as pets. If you sell those as breeders then you are continuing on the "undesirable" trait as they will also produce carriers.
There are blue programs and that is OK if their desire is to produce a better blue cat, I have no argument with that, however no-one I know has a melanistic program. I do not believe that a melanistic confers any more benefit to a line than a brown of similar breeding, but it can complicate matters if you end up with lots of smoke or melanistic kittens. The whole point of breeding is to select traits that you want, not to introduce elements that you don't want and then spend ages trying to get rid of them. It is possible in the case of snow, blue and melanistic to do a DNA test to find out what individual cats carry, so it is not a disaster, but a little forethought may prevent a lot of extra cost.
Silver is a lot easier as the cat is silver or it isn't; there is no carrier status, so far easier in one mating to select for it if you want it or select against if you want to rid your lines of it. (snow silvers can be more problematic).
If you definitely want to breed your blue girl then find a lovely blue stud to breed her to.
(by "undesirable" I do not mean they are ugly or horrible, I just mean from a purely breeding point of view those colours are not fully accepted by the Bengal breed and unlikely to be so in the near future)