Interesting and fun adventure for sure.
The first combat is a slug-fest. The enemies in this part aren't very stimulating (high HP/AC and don't do much) so the fight drags out, especially if you have an above average party that can put up a fight. My advice is to use the higher party-strength adjustments just to get this part over with in a timely manner.
The middle section (travel) could have done with a few more interactions, but it was a great aspect of the adventure.
The final encounter is quite busy, with a fair few extra things to keep track of. Prepare yourself thoroughly for this encounter; you won't regret it.
Overall, this is a well-made adventure, with a few minor inconveniences that are easy to adjust.