I use BaseCamp and agree it's pretty clunky, though it hasn't crashed on me. I hear strava.com is pretty good for performance analysis, though I haven't used it myself.
For mapping, you can use the
GoogleMaps CueSheet bookmarklet with Google Maps in any web browser: it's limited to routes you can draw in Google Maps.
BikeRouteToaster.com and
RideWithGPS.com both let you switch on the fly between Google Maps and OSM (Open Source Maps). OSM often has better bike path data than Google. You don't need an account to use BikeRouteToaster.com; RideWithGPS.com requires logging in to create routes, but registration for an account is free. All three let you download GPX files or directly to your Garmin via Garmin's Communicator browser plug-in.
You don't need BaseCamp to transfer GPX files to/from your GPS. You can use LoadMyTracks or HoudahGPS, both freeware. You can edit GPX routes graphically using Adze, which is shareware ($20). All 3 are available from
MacUpdate.com