Is it really that much of a problem to keep one extra drive icon on your desktop, and to manage files between the two volumes?
No, it is even better. Especially when you use more than one computer. With all working files on a separate volume, you can use 2 or 3-way syncing between computer 1, backup 1 and computer 2, or 1 computer and 2 backups. Even with Windows or Linux. Synkron is a great free tool for multi-direction incremental backups/syncing.
It makes all backup/clone volumes with your working files identical and you can use them all to work on. With Time Machine you it is just restoring of day X of your main volume, and not much else. If you edit a file on a Time Machine backup from a Windows machine, it goes nuts. Time Machine is fun for dad who does not need to think about his backup strategy, but if you use your computer professionally, please stay away from it and have a separate physical data volume.
Keep the SSD just for applications, settings and the OS, and make a TimeMachine backup of just that for situations where the OS disk goes wacko.