I've just seen that Jon has posted a couple of tips for BizTalk development. Just to add my tuppence, Adding
GACUtil -i
as an external tool to VS.NET really helps when you have those situations when you have changed the implementation of part of an orchestration but haven't added any new ports, pipelines, etc. When combined with RestartBT.BAT (from Jon's post) which you can also put as an external tool, it saves a bunch of time unbinding, undeploying, redeploying and re-binding the orchestration.