SABER STYLE HILT VARIANTS:
DOUBLE SABER STAFF: Everybody loves Darth Maul's double light saber, and it is indeed fun to spin! Here is an example of a double saber. Note the various places where one can place the hands, rough surfaces vs smooth. Along with the option of having one or both blades activated, and possibly at different lengths. The only limitation of any hardware configuration is fixed length. Usually, hardware is fixed.
The design of the saber, again, is all about preference. One hilt could be longer than the other, different blade lengths, etc. COUPLER vs BLADE LENGTH NOTE: Keep in mind, when you have two average length sabers joined together, the coupler adds weight. You may also wish to have another set of blades that are shorter when in staff mode. When in single blade activation, the length of the hilt can be compared to a Saber Pike, however the Pike's hilt length is usually much longer.
CAVEAT: In confined spaces, a light saber staff could be at a disadvantage in terms of movement. Wide-open space is the best environment for expression of this tool.
CURVED SABER HILT: This is a unique variant of the saber. Many SW fans will remember Count Dooku and Assajj Ventress in particular. Its curve is akin to that of an Epee foil handle, and its movement responds slightly differently to that of a straight grip hilt.
Ventress took it a step further and created a combined double bladed, curved hilt staff. A saberist should take the opportunity to train with such a weapon. While the structure is different from a straight staff, the operation is very similar but adds some unique options.
The unspoken rule here is Torque. This is most certainly a more agressive style saber, again, used in the preference of the wielder.