I'd wait around for a 50 or 75% off coupon. I'm at almost 100 hours in and decided to drop $12.50 for 1000 platinum with a 75% off coupon.
I'm finally now just getting comfortable with the game. The amount of content is staggering. I'm still not doing a lot of the content there is.
If you're the type of person who likes to collect everything in a game, there's a good chance you become addicted to this one. There's an amazing balance of warframes, weapons, and mods to keep you occupied. And because there's so much, I've found I don't get too upset if I miss something. For instance, if I don't end up doing the current Ghoul event in Plains of Eidolon, it's not a huge deal because it'll be back. I also didn't finish any of the warframes that just got vaulted, but there's so much other crap to do I don't care.
I will say just missing the acolytes probably sucks because that'll be another 9-12 months, and those mods are godly. But still, there are alternatives where it's not the end of the world.