I'm sure Drapes would agree - leave a length of string in the conduit to help pull things through in the future.
Plenty of bespoke faceplates available - many with brush entries - usually black - like you get on letterboxes - some poeple think it makes things like tidier - I don't!.
Building Regs limit you to chasing 25% of the depth of the wall when chasing horizontally so the wall retains some structural integrity - although it wont apply to you others might find it useful.