Sure sounds like you are ready, you're testing parameters, you have been keeping your tank for while.
You need to do all the obvious things for sps , test the whole list of parameters ( nitrate, phosphate, alk, ca, mag, salinity and temp) and you need to keep them stable. You need good flow, and your lights need to be adequate for sps. Lawman is correct, I don't know if your lighting is adequate or not based on limited info provided, so you need to confirm if your current set up is adequate lighting Year old tanks are great for oh so many reasons, stuff in the tank matures and settles in, and you have proven the test of time as well with your routine.
Start with not too expensive sps frags. Happy frags tend to have wonderful polyp extension and good idea to start with nicely colored up frags. Don't buy too many frags until you are sure your tank is supportive of productive growth (that means you have happy corals). Pests are endemic, I am a fan of Bayer dip so,read about preventing pests, lots of threads on it. Careful, sps are addictive