Spending a month's salary

I don't have much experience as an audiophile. Based on my research, the bulk of spend should be on fine speakers. I have $20k to invest in either a superior AMP, DAC or pair of speakers. What to do?

My room is on the smaller side, listening position is about 7-8ft from the speakers. I suppose bookshelf speakers are appropriate. Right side speaker is very close to side wall <1ft. Left side is open to 6-8ft. Back wall is about 10 ft from listening position. Speakers sit about 3ft from front wall.

My current setup:

Revel 106 speakers

Parasound P6 pre and A21+ amp

Node 130 streamer w/ upgraded Teddy PS

AQ cable loom.

I prefer bookshelfs given my room. Separates are ideal, though I would like to consider an all in one like a Boulder 866.

Which component is most important. I'm not looking to have an unbalanced system. Eg. $15k speakers and a $500 DAC.

Appreciate any insight.