Well...it really doesn't matter if you backup routinely...or you clone your partitions/drives routinely...what matters is that you need routine, regular backups to go to when things go wrong. I think we've all learned by now...that things WILL go wrong.
I've never found Windows System Restore worthy of being relied upon, since it does not take into account hardware or malware problems that result in the user being unable to boot into Windows to use the SR function.
I'd suggest routinely backing up, using something like Macrium Reflect FREE Edition - Information and download - http://www.macrium.com/reflectfree.aspx
As for external drives...those are nothing but regular hard drives within a USB enclosure. Their weakness is that they give users two or three points of potential problems, as opposed to those presented by drives connected internally. The enclosure itself...the drive itself...anything relative to the connection/transmittal of data between system and drive...all are potential points of failure/concern.
As for "optimizing" an SSD...not sure what you might mean. Nothing manmade is going to last forever or work perfectly over time. Look at the warranty period for that drive and you will see how long the manufacturer expects it to be without problems
. No purchaser/user of such should have more confidence than the manufactuer, IMO. If problems arise before the warranty period expires...well, that's what the warranty is for and that's why it's good to have backups.