CoS2 is a good FM. It is probably the earliest FM that isn't really showing it's age at all. It's enviroments are detailed.
The only place that this mission does fall apart is the water; it's a bit buggy.

If I was to level criticism, it would be aimed at it's loot objective, which requires almost literally every piece of loot on the map. That sucks. There is also the fact it's a kill objective: while these are common in these early FMs, it's still a break from what thief is typically about, and while I can give it a pass in situations where we are playing someone who isn't Garrett, here I can't.

Both of these are fairly minor though. The mission is small enough that you will find the loot fairly quickly, and the thing with the kill objective is little more than a nitpick. This mission is good. If you have a spare 30 minutes, this is a good place to spend it.

I remember that when I played this level the assassination objective was actually one of the positive highlights for me. While Garrett is not necessarily a murderer, in Circle of Strain 2 the killing can be done very stealthily without alerting any guards, so it is not too removed from the original gameplay.