Not Universal, but I went to both SWO and BGT last year mid-week *before* President's day weekend, and it was dead. I had the QuickQueues but did not need them at all.
Most of the schools in the New York area (and maybe other places in the NE) have the entire week of Pres Day off so it tends to get very crowded that week at the parks in Orlando. I would factor a fastpass into your plans or stay on property at one of Universal's deluxe hotels which include fastpass for everyday of your stay, including check in and check out day. We always stay at the Royal Pacific and in my opinion the price is reasonable for what you get and if you compare buying fastpasses on top of cost of hotel somewhere else it really is fairly economical, particularly if you have more than one person in your party.
Same reason it takes a lot longer to refurbish a classic car instead of just building a brand new car at a factory. When you’re (presumably) keeping many of the original components extra care needs to be taken.
Not sure if it's come up but Universal put out a official POV of the Hagrid coaster with the audio recently:
I think before that, there were only unauthorized recordings which couldn't be shared on this forum. I haven't been on this ride so I'm not sure but it seems like this video has been sped up or has some kind of motion blur effect on it.
I don’t think you have any idea how complex converting the ride to a different launch system really would be. 6 months would be considered a fast turnaround…
you need a new train, new electrical system, new control system, structural modifications, training the crew again, getting state certification…