How do you mentally deal with the risk of having your emergency fund in a S&S ISA where (presumably) there's a good chance that money gets eroded as markets fall? I know long term it balances out to generally be up, but shorter term it's harder to deal with volitility. I'm considering having my emergency fund (of a few months' salary once I get there) in NS&I Premium Bonds with a local "buffer" pot of £1k just sat in my bank account to cover the few days it'd take to get money out of NS&I - I also have a credit card that I could use should the emergency be bigger than that.
As for savings, I've budgeted quite heavily for when me and partner finally (if ever) get into our new house, but living with her parents for the past few months mean I'm debt-free for basically the first time in my life. I have a good few thousand in various pots in my bank account, including a 2-month emergency fund which is growing, a smaller general savings pot, as well as segregated areas (or Spaces in Starling parlance) which I use for monthly direct debits to come out of, as well as an "Annual" space which I contribute monthly to enabling me to pay for yearly things (annual rail ticket, car insurance etc) without getting penalised for direct debits etc.
Once we're in the house, I've got a self-imposed "red line" that 25% (so this'll be about £550/month right now) of income will go into savings of some variety. The emergency fund will contributed to heavily at first, and then look at getting investing in a S&S ISA, likely just the Vanguard LifeStrategy 80/100 to get started.