Thanks so much for playing, and your feedback! I'm glad you enjoyed it. :D
You aren't the first to mention the walking speed, and a sprint would be a fairly easy feature to add. (Famous last words lol...) The only section that does come to mind is the sewer chase, as you'd mentioned... I might be able to get away with simply making the area longer and requiring you to sprint to win... could even help add a little intensity to it. Thankfully that section is created with seamless tiles, so extending it is very doable.
Huge shout out to Facemelting Solos who created the full soundtrack for this game! We've worked together a number of times, and though this one was a completely different mood, he nailed it again! Couldn't do it with out him!
I've got at least 5 more chapters planned, I hope you'll check them out when they are ready! (Not setting a deadline though, I have a history of that, and still have 2 other games in need of finishing ^v^; )