I've been thinking about this for a while and thought I would put it into a blog post, noone has done a line up of the next battle against Vandenreich which in all likeliness could be the final battle, anyway here is the lineup as it appears so far, feel free to critique this listing if I miss something (please keep in mind this is largely conjecture combined with some known facts):
Soul Society/Hueco Mundo:
Gotei 13 Captains and Lieutenants: Counting all the remaining captains and lieutenants I counted 24 because Mashiro is shown to be a lieutenant again and I think we can count Yamamoto, Unohana, and Chōjirō Sasakibe out of the picture (Kira is still completely unaccounted for so rough estimate here), altogether there is known to be 10 bankais that can currently be used (if they can figure out how to keep them from being stolen).
Royal Guard/Zero Division: 5 members with a combined power exceeding that of the entire Gotei 13.
Fullbringers: 3 of the Fullbringers were shown and we're not entirely sure what powers they still have as Ginjou at one point had Ichigo's fullbring and copied his powers but we don't know if that is still the case.
Remaining Arrancar: Tier Halibel's Fraccion, Grimmjow (possibly).
Shiba Clan: Ganju was mentioned to be taking part in the next fight, Kukaku is unknown at this point.
Kurosaki's: Isshin would be a likely candidate to take part in the next battle and obviously Ichigo will be fighting as well.
Gotei 13 regular forces.
Soul King: Completely unknown variable here as he may or may not participate and we have no idea of his abilities.
Team Urahara: Fastest known practitioner of Shunpo as well as Captain level power, so tough she doesn't even bother using her Zanpakuto, 2 super powered kids, and the former captain of the Kido Corp who boasts a wide array of forbidden Kido techniques along with all the known ones, and of course the smartest Shinigami of all time Urahara himself who despite having been involved in several battles always seems to have an Ace up his sleeve not to mention, based on how powerful his Shikai is, a quite possibly insanely power Bankai.
Stern Ritter: Unknown total force with control over at least 5 bankais. (would be 6 but I don't think that Chojiro's bankai will be used anymore)
Soldat: Unknown total force with unspecified power level.
Jagdarmee: Unknown total force with unknown power level who may or may not be involved in the upcoming battle, however it would seem likely they will participate due to the fact that the VR seems pretty determined to finish the job in the next fight.
Stolen Bankai: I felt it important to mention this due to the fact of the pivotal role that they could play in the next battle.
Zanka No Tachi: Most powerful Fire type
Daiguran Hyorenmaru: Most powerful Ice type.
Kokujō Tengen Myō'ō: Giant with massive amounts of strength.
Senbonzakura Kageyoshi: Massive amounts of mentally controlled blades.
Jakuhō Raikōben: Missile with devastatingly destructive capabilities.