Chance Morgan & Vekoma recently announced an alliance, and they're both going to be involved together in what seems to be a few projects for Hard Rock Park. I wouldn't be too suprised to see a Rollerskater, but I'd expect some flat rides from both.
The new Jr. Hyper going up in Japan at USJ is a Beemer with an audio track. We already know that the Beemer going to HRP is going to have an audio track, and since HRP is right beside MBI Airport, don't expect anything too tall, a Jr. Beemer with an onboard soundtrack would fit right in (although I'm not saying for sure as I don't know, just a best guest).
Premier makes coasters...And towers, and flying scooters, and other flats and transport rides. But initial rumors suggested a launched Premier set to music as well, so that could happen, it may not. I don't see them building an observation tower, though, because of the airport.
I just hope Huss is contracted for something with the words Giant and Frisbee in it, but any Huss ride should be good.
Sally is definitely going to provide a dark ride, duh!

. You could definitely build a brand new park with the companies provided, with coasters, dark rides, interactive attractions, family and thrill and kiddie flats, etc. I honestly think Hard Rock Park is going to be better than what I initially expected...