Both the power creep and the ongoing watering down of the factions is not doing anything for my excitement.
At this point having real factions doesn't even make sense anymore.
Every race/faction should have a starting world/base with some exclusive tutorial content and then it's out into a sandbox galaxy with faction neutral missions.
Access to certain systems would then be restricted for certain species and ships unless they have advanced in diplomacy enough.
Honestly, what you want was only done by the first generation of MMOs such as UO, EQ1, AO, DAoC back in the 1990s. Very few subsequent MMOs have even dared to do this unless they had a massive budget. Quite simply, it does not make financial sense to create content that only half your players cannot see.
So unless you can give Cryptic $10 million and a year to make new STO zones, what you are asking for is quite impossible.
In terms of sandbox MMO's, Black Desert doesn't look too bad, though it is fantasy based:
"Black Desert is a large scale sandbox MMORPG that provides you with a variety of unique experiences with spectacular action and battle, strategy-oriented castle siege, sophisticated simulation contents such as trade, NPC-hiring and real-estate management."
"Combat has been described as a hybrid between third-person action titles like TERA and Vindictus, and FPS-style systems like those in the Elder Scrolls series."