Brokerage Account as Part of Emergency Account

Ive been doing this for a while now and wonder if anyone else does. I have read through some other post on here discussing the use of a roth and other types of accounts. Ive been putting about 1/3 of our emergency fund in my brokerage account buying commission free etfs. Most of it goes into USMV. A minimum volatility large cap etf. I also put some in SHY and TIP, a 1-3 year treasury etf and a tips bond etf. The money is fairly liquid. We put about 400 a month in the emergency fund, so about 130 goes into these etfs on average every month although some months Ill put more or less depending on what the prices are at. As long as the shares I would sell if an emergency came up would also be commission free since they have been held for over 30 days as is the policy for my brokerage account.

The other 2/3 go into a standard savings account connected to our checking.

Im thinking about starting to put about half instead of 1/3 from here on out now that the wife found a position.

Just wondering if anyone does the same thing or has any opinions on this practice.

Thanks.