We have a similar situation, with a 9ft garage door that measures about an inch less clear opening due to hinges and garage door hardware.  Our old T1N Sprinter fits but newer NCV3 Sprinter based Class B's are too tall.
We found only a couple options for a newer and larger replacement - custom conversions of either a medium roof Ford Transit or high roof Ram Promaster.  Both will fit under the 9ft door but without rooftop air conditioning. The medium roof Transit is limited to 5ft 10in interior height and 20ft max length; not enough standing height for us six footers and didn't really gain much interior space due to the medium roof length limit.
That leaves the extended length (21ft) Promaster high roof as the biggest interior van that will fit under a 9ft garage door. And that extended Promaster feels pretty big inside, probably due to the combination the low floor, short nose, and significantly wider width than our Sprinter.
You mention not wanting a Sportsmobile. Is that a dislike of the brand or simply not wanting a poptop roof? The reason I ask is because Sportsmobile is the only converter we've found that installs the Danhard chassis mounted air conditioning system (often used in ambulances) on a Class B conversion. High roof Sportsmobiles don't have (or need) pop-tops.
Other custom converters can build a Transit medium roof or Promaster high roof that fits but without rooftop air. Or you could even try removing the AC from a factory built unit like Roadtrek's Zion or Winnebago's Travato. But Sportsmobile appears to be the only option for a full height Class B with air conditioning that fits under a 9ft opening.
I'd be interested if you find any other options.  And BTW the Sportsmobile folks in Austin Texas have been very friendly and helpful in answering questions. (But heads up - they have a long lead time for conversions).