The idea behind Galactic Command is solid. Reward players for experiencing all types of content (instead of just operations) so they don't get bored. RNG has always been part of the game, and 224 set armorings can still be used in 5.0 alongside 230+ mods and enhancements if you get unlucky. There are three main issues I see:
1. Players want to be able to do every type of content within a few weeks of playing, not months. This can be fixed by reducing the level requirement for t2/t3 and making set armoring more common and transferable to other gear slots.
2. Hardcore players will be inclined to do the exact opposite of a diversified playstyle, as they'll grind the content which rewards the most CXP per hour. This can be fixed by increasing the rewards for dailies/weeklies.
3. Preferred players are completely gated out of the endgame. This was an issue in 4.0 as well, and can be fixed by offering alternate payment methods.
To sum it up, I think the system gets a bad reputation. It sought to diversify the playstyle by shifting it away from Operations grinding, but the byproduct was making it worse for players who are used to Operations. This can be fixed, and it wouldn't be too difficult to do so.