Pretty much live by these in practice... I've had a lot of arguments over #3 though... yes nested loops can cause problems... but when you're dealing with < 100 or so items in each nested loop and outer loop, it's not a big deal in practice. It's simpler and easier to reason with... don't optimize unless you really need to for practical reasons.

On #5, I think most people tend to just lean on RDBMS databases for a lot of data access patterns. I think it helps to have some fundamental understandings in terms of where/how/why you can optimize databases as well as where it make sense to consider non-relational (no-sql) databases too. A poorly structured database can crawl under a relatively small number of users.