Re the Sky90, I hear the Borg 90FL takes a similar approach but is
better executed.
I have been very happy with the FS-60/FC76DCU package for years now (95% visual). I'd imagine the Q extension would be an upgrade to the bare FS-60, but with the FC76 objective unit I've never felt the need. I could always stop down the 76 back to 60mm to make it an f/9 fluorite doublet if somehow the 76's image quality wasn't good enough at full aperture. That has never happened so far. The scope still gets used in FS60 mode often because the entire setup is ready to observe in under a minute. It's still my most-used telescope despite ready access to a range of instruments up to 18". Recomendation to OP is therefore the FC76 DCU (with the split tube) or, for a bit more reach, the Borg 90FL.