This is science fiction from 1980 and is therefore not obsessed with:
1) Computers.
2) Nanotech.
3) Wormholes.

This makes it rather refreshing. Instead this book uses an old theme, prevalent in post-WWII American SF: Humans (read the USA) are superior to everybody else. In this example, humans are technologically outclassed by every other space-faring species in the galaxy but are superior because their intelligence evolved naturally instead of being the result of genetic manipulation by an older species. Or maybe not - it's the hottest debate in the galaxy. Various species think humans are upstarts. Others - usually also younger species - kinda like humans. Devious, nefarious politics ensues and our protagonist gets caught up in it.

A slow start leads on to an exciting Poirot-style murder mystery and then a further action-adventure in the chromosphere of the sun, where life has been discovered. Apart from being a compelling story, the main interesting thing in the book is this sun-life. I'm sure I've come across the idea of star life before but never in as much detail.

Inevitably this is the first volume of a series; I'm inclined to carry on with it if I spot the remaining volumes.