Can't remember which episode, but Bra'tec had a cilindrical shaped Goa'uld ship hidden that he and Hammond used to travel through gates to defend the other heroes.
I never saw anything like that again and I wonder why not. It would obviously have been a great addition for the SGC expeditions as was shown in SGA.
I wonder if the water dwelling parasite from the planet where Cha'kra took Daniel is the same race or even species as the Goa'uld symbiote. I can believe they can control the more animalistic minds of Cha'kra's people as part of their procreation process perhaps but I don't think they're usefull as Goa'ulds because obviously they have no relevant genetic knowledge to the system lords.
The Goa'uld species I think diverted long ago and these water dwellers are comparable to our Homo Neandertal or something like that.