New surface types are not possible. You can create new surface templates in the editor and while these are functional, the amount of the surfaces in the game is hardcoded into the engine. So you would have to override a surface in the game if you wanted to make a new surface.

it's a pity

Is possible in theory bounded new custom surfaces types to default types, like default electric water [1)primary - water + 2) secondary - electricity] to water + luminary energy or not?

Is possible to add perk like effect to custom attribute like life steal from necromancy, stat bonus from polymorph or attribute with no magic school like damage reflection?