Welcome to the Forum BobR. Your problem is common and hard to fix. Some phrags are reluctant to grow. You can repot them and hope you get the right mix. You can change the light, the watering schedule, use more fertiliser or less, change the formula and nothing works. I have phrags like that who seem to take forever to get somewhere while those around them are thriving with the same water, the same light, the same fertiliser, the same ventilation. My feeling is it's a genetic disorder. The plant is simply a weakling that should never have been on a sales table but on a compost pile. And when we invest time, even years on those, it's hard to call it quits and throw it out. I'm learning hard to do that, to part with plants that show no sign of going anywhere. Next time you see something on a sales table, don't be afraid to ask questions like 'How old is the plant?' How do you grow it? Can I see the roots?' And if need be: 'Do you have anything bigger?'
As far as the variegation is concerned, it could be missing iron in the mix. I've had that problem recently and I put a pinch of iron dust in the water and the plant is going green again. Try garden centers if you want to find it or maybe ebay. Good luck.
