The beginning of the adventure is the usual dross of encounter after encounter with predestined outcomes, that TSR was so infamous for at that time. But the later parts suddenly change into a lot more freedom for the party with multiple locations on offer and multiple endings possible. The big infiltration missions at the end feel so much better than the first half with lots more options and characters. Plus it genuinely describes what is going to happen if the party doesn't do anything and it is up to the party to influence it (or not).

Some of the fights probably need a bit of rebalancing and the "enemy will normally not flee" more issue is also fixable if wanted. I could also image just inverting the whole adventure if a rogue is in the party.