Switch to Lightning UI without changing Classic UI

Dear all,

hope this will not be a question that has been placed already.

We would like to create a LEX UI without influencing the layouts for the classic version. But the LEX UI should sure look different. The goal is to give the users the possibilty to switch between LEX and classic without changing the profile.Therefore the classic UI should look like always independant which changes I do in the Lightning page layouts.

I found a workaround that works quite well for admins. I created new tabs in Lightning for each object and added a new related record that is filled with a quick action "Update Record". The original tab with the classic view I did not touch.

Therefore I have no changes in the Classic UI but only in the LEX UI. But this does not work for "normal" users as some fields are Read-Only and therefore I do not see all fields.

For me it would be very interesting if someone would have another workaround or do I really need to create a new profile?

I attached a screenshot to explain.

Thanks already for your help.

Martin