See an example of transport unions in the UK. Tube drivers are in the top 5%/10% of income in the UK, for a 35 hour or so week, and a lot of other benefits. The union power has done amazing things for them... but at a huge cost (albeit dispersed) cost to the rest of society.

Fully agree the ideal is where you have both. Germany seems to have good models where unions improve the efficiency of companies in giving a point of contact for negotiations, and helping the company succeed - winning together.