I also tried the cMIUI youre referring to but it had the common SD mount issue, cant see it. Ive used Directory Bind etc in the past as the OP admitted they havent fixed this yet but every now and then the bind wouldnt work or on reboot i had to reenable it etc so it became a nuissance regarding not being able to see my SD.
I am currently on RGUI MIUI and this feature works perfect. It always sees the SD, ex SD cards no problems.
Can you confirm if you are having problems seeing your SD with such a 3rd party app as this is a clincher for me moving back over because as you said, it would ideally be the best of 2 worlds.
This RGUI looks perfect, pity we will not have v5 which is only for s3 and development stopped on v4 for s2
would like to have beast audio and bravia engine.
Edit: after some test it doesn't work correctly. SMS notifications in lockscreen don't work - you must unlock and then lock back to see it on the lockscreen (this doesn't work on all 2.8.3 stock based roms, for me it only works on CM9) and also "Network Operators" setting FC the phone application.
So here is my comparison of MIUIs 2.8.3 based on different frameworks for Galaxy s2:
Stock based MIUI:
+ good display and auto brightness control
+ great camera
+ stock FM Radio
+ external sd card works correctly
+ good transfer speed over mass storage ( up to 8 MB/s)
- lockscreen sms notifications don't work
- Phone app sometimes FC (if you try to open "Networks Operators" settings)
- 2s lag on home button (because of voice navigation stuff)
CM9:
+ great speed
+ all setting work fine - no FC
+ sms notifications on lockscreen works fine
- strange auto brightness control - it is very sensitive so it changes brightness constantly and is very annoying
+ no home button lag problem
- no FM radio - need to use 3rd party app
- camera app usability not as good as stock camera (subjective)
- very slow transfer speed over mass storage (only 2 MB/s - CM9 issue)
Hope somebody someday will fix all those issues and we will have great rom. Because I think, MIUI is the best.