First of all, for RoS raids, it should be RoS T2 group gear (perhaps the tanks would use some T1 non-visible items as some slots have more AC for some odd reason) for your scenario. Some work is required if you want to raid latest content in group gear -- e.g. getting the latest group gear. Secondly, many of these raids can be beaten with less than full raids. If you want to do them in group gear, then make sure you have a full raid force. That makes up for possibly needing more tanks or more healers. You just need dps that actually does their job somewhat near their potential (lesser gear taken in to account) for smaller forces and a roster tilted more towards tanking/healing. And while such a raid force is working on getting all the flags to enter t2 RoS raids, they can be using their extra raid schedule to beat EoK raids and be getting EoK raid gear (needed to make the RoS visibles anyhow). Raiding does require some character development through gear, augs, AA and such.