They go to the future in the Black Moon arc. Yes, they are as far as I recall wearing their uniforms... however they are also only used as batteries for a
force field on the castle which is alll they can do. There isn't any visible population (though they could be off screen in shelters (possibly under the
castle) or something rather than dead), and they are clearly losing this battle... which is why they have to call in their past selves in order to take down
the enemy. To be frank they aren't exactly shown to be shining paragons of competence... they are being overrun by a splinter faction of their own once
citizens.
By the time we get to see it, Crystal Tokyo is overrun, though shiny, and they have all but lost a basically civil war. 3 Senshi are completely AWOL and they
are in a darkest hour scenario. So seeing as the lot of them have all of one offspring (apparently less than a decade old) and all their shown citizzens are
actively trying to kill them... I often wonder why people think it would be such a great place. Lets not go into the theory that their are less than 20 people
left on Earth at that point theories.
Reguardless of if the Senshi can activate their powers out of uniform or not after X centuries, the uniforms will enhance them regardless. That is the point
of them. Mars' power shown out of uniform are things she was trained in beforehand. Mercury can use the computer outside of uniform, but its equipment.
Saturn shows healing powers outside of uniform... but she could have learned those as a result of Mistress 9 possessing her. Mistress 9 was actually training
her body to use magic effectively. Neptune has equipment powers out of uniform. Jupiter's super strength burst could have to do with her martial arts
training.
Even taking into account they've had X number of centuries to train they could have learned powers the normal research and practice way anyway. Yes, they
have elemental affinities and it would be stupid not to exploit that for training... but saying they can use non equipment based powers outside of uniform is
unsubstantiated. So I don't understand why she would even need to be able to use Senshi powers outside of combat if she didn't have to. Also consider
that Crystal Tokyo is suppose to be a magical kingdom and it would be rather difficult to pull that off with on a handful of random magic users... having a
magic school only makes sense.
force field on the castle which is alll they can do. There isn't any visible population (though they could be off screen in shelters (possibly under the
castle) or something rather than dead), and they are clearly losing this battle... which is why they have to call in their past selves in order to take down
the enemy. To be frank they aren't exactly shown to be shining paragons of competence... they are being overrun by a splinter faction of their own once
citizens.
By the time we get to see it, Crystal Tokyo is overrun, though shiny, and they have all but lost a basically civil war. 3 Senshi are completely AWOL and they
are in a darkest hour scenario. So seeing as the lot of them have all of one offspring (apparently less than a decade old) and all their shown citizzens are
actively trying to kill them... I often wonder why people think it would be such a great place. Lets not go into the theory that their are less than 20 people
left on Earth at that point theories.
Reguardless of if the Senshi can activate their powers out of uniform or not after X centuries, the uniforms will enhance them regardless. That is the point
of them. Mars' power shown out of uniform are things she was trained in beforehand. Mercury can use the computer outside of uniform, but its equipment.
Saturn shows healing powers outside of uniform... but she could have learned those as a result of Mistress 9 possessing her. Mistress 9 was actually training
her body to use magic effectively. Neptune has equipment powers out of uniform. Jupiter's super strength burst could have to do with her martial arts
training.
Even taking into account they've had X number of centuries to train they could have learned powers the normal research and practice way anyway. Yes, they
have elemental affinities and it would be stupid not to exploit that for training... but saying they can use non equipment based powers outside of uniform is
unsubstantiated. So I don't understand why she would even need to be able to use Senshi powers outside of combat if she didn't have to. Also consider
that Crystal Tokyo is suppose to be a magical kingdom and it would be rather difficult to pull that off with on a handful of random magic users... having a
magic school only makes sense.