If you had to start all over again in this day and age

Not too long at all Kren. I know noting of streaming. Don't know what to buy or where to start. Speaking of hobbies, one of mine was photography. It took me 30 years to get into digital. One trip to Alaska and 700 shots later, I never looked back.
I'm hoping streaming would be kind of the same thing.
Unfortunately, I am not a "music listener". I am a component listener which is way bad. It was different when I could listen to just about anything I wanted and took stuff home from the stores but it's where I picked up this bad habit of listening to "equipment". Hence my trepidation getting into streaming. 

Nearly 40yrs an audiophile and I wouldn't change a thing with the budget I've had over the years. I ha e what I think sounds best for my taste, room, music, and the money. I think a better question would be: if cost was no object what would you change (room stays same)?

I’m good.  Always considering technical innovation when buying. 

I'd go with smaller main speakers.
I'd have at least 4 subwoofers, maybe 6.  
I'd go with Class D amps. 
I'd own no vinyl or cd's....streaming only.
I'd keep my tube preamp.
I'd spend more money on a DAC.
I'd own a 10 inch reel-to-reel just for show....as audio art.
I'd own a late model Oracle Delphi turntable just for show...as audio art.

I'm good right where I am.