Inviting can be difficult
A lot of the missions are very much the same
Everything is obtainable by playing the game for long periods. Yes it wants you to buy platinum but that's because they know how impatient people are, you can pay to win essentially but it only effects yourself as it's a co op game...
The fun is trying the new warframes new weapons and just generally collecting treasure, the fun is getting a blueprint and then having to farm all the resources, then after a few days you have what your were trying to build, and it makes it that much more satisfying.
I love this game and I'm glad I tried it when I did...
First I did try it because if lack of games on ps4 but now it's just brilliant the more you progress the more interesting it becomes, seeing how long you can last in a survival etc collecting prime parts to build rare weapons and frames...
So yes James I would still play it if there were more options on ps4, put it this way I have watchdogs, I played the first mission, haven't bothered to play it since warframe is just too interesting for me right now...
Also, technically this is meant to be an open beta... There's a few bugs and glitches but even since Iv played it's improving all the time, so much new content is being released all the time. It's well worth a try IMO...
EDIT: one annoying thing about this game is there's no explanation about anything, everything has to be learned by yourself and passed on to new players, like it has been in here lately, it's very confusing...