I easily manage 3 nights or so with no framebag – and that’s in a non-competitive environment.
There are loads of threads on here featuring soft luggage; you’ll get proper user reviews if you search through them.
A small backpack might be a useful addition, even if it’s just for carrying food and/or a spare layer of clothing.
Gas tank/Fuel tank/Bento box/Feed bag style bags are handy for camera/snacks/tools etc.
My stuff is all Revelate. At the spendy end of the spectrum but well reviewed, used extensively and with great support. Available from backcountrybiking in Aviemore.
Wildcat/Alpkit/Apidura are all out there too.