Investment strategy for brokerage account with goal of buying a home in 1-2 yrs?

I currently have just over $100k in a brokerage account with $90k in the core position (spaxx) and $10k split evenly between two different bond etfs (SHV and BSV).

I am having a hard time understanding the benefit (if any) of investing in bond etfs vs just leaving everything in spaxx - will bond etf dividends still generally yield more or is the main benefit that you can get some appreciation in principal? Is this enough to even make it worth it?

Looking for suggestions on how I should structure this portfolio with the plan to add ~$1k a month to it and use to buy a home in a year or two.

Thanks in advance