chess pieces can have two sets of movement rules - they either move, or move and capture. the set of moves you make to capture can be different from the set of moves you make ordinarily.
these move a set number of places orthogonally in each direction - the knight is a (2,1) leaper. they usually use the same move to capture.
some of these have designated names in muslim versions of chess.
wazir(1,0) dabbaba (2,0)
fers (1,1) knight (2,1)
a king can move like a wazir and a fers.
an alibabba can move like a dabbaba and an alfil.
these ones are also named on wikipedia, but they don't sound as cool. It'd be a good idea to invent muslim names for these pieces.
riders move an unlimited distance in one direction, but cannot pass through other pieces. In a orthodox chess game, a rook is a (1,0) rider, a bishop is a (1,1) rider, and a queen can move like a rook and a bishop.
you can extend any leaper to make a rider - knightriders, (2,1) riders, are pretty common. generally, the nomenclature is just to stick -rider on the end of the name.
hoppers move by jumping over other pieces - in those cases the pieces are called hurdles. A hurdle can be any piece of any colour. in chess variants, the hopper usually captures by landing on the same square as the captured piece. A hopper that captures pieces by jumping over them - as in checkers - is called a locust.
you get pieces that move as leapers or riders but capture as hoppers.
you also get hoppers that move as leapers or riders, but which must end their turn with a hop. The grasshopper is a hopper than moves like a queen but ends with a hop.
possible general nomenclature for this would be some prefix like assassin - so the grasshopper would be an assassin queen.
The special thing about making chess-based tactics games is that units are fragile - do not have hit points - and are limited. This is worth preserving even as rpgtactics stuff is added.
what rpgtactics stuff could we add? defender classes that protect nearby units. constructions like walls, etc. probably a bunch of interesting setting stuff.
i'm not sure if i would want to make it a one character deal, like chessrogue.
unit prototyping, as in diablo, or as in 4x space games - alpha centauri is the one i think of.