The CRM system (used well) is crucial for that. How long are you spending on average doing CS work? Are some customers more expensive to service than others? Ar

The CRM system (used well) is crucial for that. How long are you spending on average doing CS work? Are some customers more expensive to service than others? Are you charging enough (patio11 says no) to cover the costs of customer service? If you're not then no amount of growth will help. If you have companies requiring Enterprise level support and you're charging them Startup prices then something needs to change. There's also a level of intellectual honesty required about how mature your product is. You may be spending ages dealing with some customers because they aren't early adopters and your product isn't yet ready for their needs.