The Summer event and New Romulus put a whole light on the STO world for greater potential. The game is about space and so massive emphasis were placed on the space components. However I love running along the sea side or exploring new and interesting maps. If you could start converting the old worlds one by one and mid ones slowly at a time expanding them with more opportunities. This would introduce potential for player:
Which would bring in more PVE and PVP content for eg. say the Klingon Fleets or Star Fleet decide to take over a planet others could vie for that planet and enjoy the fruits of it. Develop the planet into a striving system by pumping back resources into it or turn it into a wasteland by keeping the resources for yourself which both in turn would give big rewards equally. Since other fleets would be trying to take back these planets. Fleets could ally together and more transwarp options unlocked for high level fleets. Resources could be in the form of:
Fleet, Omega and Romulan marks dailies.
Planet security from space to give warning about approaching ships so battle could start from space to ground.
find rare tribbles, capture critters
new weapon modification options
Ship paint and home world branding
Player housing would be rather easy to implement into STO as you can simply create preset and sell designs in the C-Store I do not suggest furniture grinding as in other games just a place one can go setup a one or two bedroom place and spend his days doing his crafting instead of flying to memory alpha. Furniture is already in the ships and those can be used without creating new models, etc. Allow trophy decorations, this would tie in with more open world content instead of parking in space for hours doing nothing as I see many do. Let the bridge officers appear in the home and relax grab one and explore the world for dangers or great finds and this could start with 5 planets and expand outward and I bet you could find so much more ideas to add to this to make it epic. Risa made me think as I stood on the top of a mountain and a lady landed beside me thinking of the same things. She even thought what if she could move in with me lol... Thats another story be ye inspired.
Player planets would be a great addition to the game plus it would allow you to experience the trials that terraformer's or colonizers get when they get access to an uninhabited planet, terraforming would allow you to pick the design and look of your planet and colonization would allow you to have more Duty Officer missions.