Currently the "Store page" says, "Colony Ship is an isometric, party-based RPG".

Despite this, the screenshots present on the "Store page" are clearly third-person-perspective and not isometric at all.

Will you add an isometric option?

A true isometric option is impossible at this point.

As for the store page, the vast majority of players associate third-person perspective with over-the-shoulder view (Mass Effect, Gothic, etc) while isometric with angled overhead view, which includes trimetric (Fallout) and perspective projection (Diablo 3, Titan Quest, Pillars of Eternity).