I think the best way is 40:60, 40% saving the money and 60% we invest the money(btc,gold,etc). Why we must save the money? Because a lot of unexpected things can happen everytime.
My opinion is the same. I feel like the 40% is your fallback money, whenever the other 60% investment goes bad.
If you want to invest in a semi decent stable coin I recommend to get your money in Bitcoins. Optionally you could also get 10% to go full insane with investing in small coins to (maybe) get some big profits.