If you have $50k do not invest in big coins like sia, monero, eth etc.
You need to find a coin that have huge potential to grow. If you ask me, the answer is Shift. Invest in before phantom release and potential poloniex listing. You can still buy cheap Shift. It will make you millionaire in a year.
I have to say i agree with you and i actually wanted to put Shift also on the list.
It depends though, right now it's kinda shady project, not much information on website and such. But it really could skyrocket, and just for the record i do hold some SHIFT, far from 50k$ though.
$10K shift would be enough for you. and hey, shift price is so good to buy now.