A couple of ideas.
First, staff must have all tools at their disposal to be able to support the users to the best of their ability. This includes ongoing training and development.
Anectdotal meetings usually help tremendously. For the support staff to tell each other stories often results in the next incident being identified and solved sooner.
Established escalation procedures are critical.
Well-detailed and published service level agreements are a must. Further, these SLAs should be in everyone's hands for distribution, sales included.
And, assess, assess, assess. You need to be like a small boat, not a cruise ship. Small boats can change course at a moment's notice. If it doesn't work, don't be afraid to scrap it and start anew.
Good luck to you,