Really good guide, and you really nailed the section early on - being alive is the most important thing.
A good tip to trying to learn to stay alive above all else is to play a longer range weapon, like the SSPro (I would recommend the Dualie squelchers as well but the dash can give you an easy bad habit in letting you expect survival at the double-tap of a button). When playing SSPro, as well as good aim, another important factor to success is being able to kite reliably, which means while playing the weapon you're forced to splatter dash backwards towards your team. Another good weapon to learn this with would be the mini splatling, though splatter dashing is harder.
Of course there are a few moments where a death is actually worth it - in Rainmaker, for example, getting the Rainmaker to 30 or below is often worth the inevitable doom that you'll find by their spawn.