So I've heard a Orc King is rebuilding Orsininium can we possible see the Orcs ever becoming a powerhouse in the near future? What are the Orc Kings plans? I love the Orcs and their culture I wanna know what is going on with them
And I figured I would ask the experts!

Not an expert, quick answer is: Only time will tell

Kingdom has risen and fallen before, suggests history will repeat itself. A "powerhouse" - I doubt it, nothing on the scale on the Empire/Dominion. A powerful, but small, state is possible, something equivalent to other high rock states. Of course, orcs are reputed for being exceptional warriors, and a good people to have on your side.

My guess is they will rebuild, and possibly get some revenge on other parts of high rock. Maybe one day "Orsininium" will be synonymous with "High rock"

Orcs only care about being able to follow their traditions alone and not be bothered. Orsinium is and always will be an enclave where Orsimer can be Orismer. Although it would be a potent player in politics given how Orcs are some of the best soldiers in Tamriel, it wouldn't be anything close to what the cities of High Rock do at a daily basis.

The only way the orsimer will grow to become a powerful nation is if High Rock and Hammerfall stop trying to wipe out the orsimer everytime the empire looks away, or convince the two countries to stop their bonding time and try other hobbies.