Be careful with the kind of tools that increase abstraction in the code base itself. It can easily tip into a situation where it will have to be all ripped out when the OP leaves the company. Or worse, remains as a cargoculted mystery.

There are no hard and fast rules, but stuff that increases the productivity of other in a (to them) non-mystical way would be best.

It's a judgement call, some of these in the list above made me pause, but the red flags will be specific to each workplace.

The keys is to know what others will understand, and that is a super-power in itself.