Liberty profile isn't exactly painful, but everything else Websphere is.
Regarding DB/2, I don't think that the installation process is the most interesting property of a database. The database is about as good as you can get, but there are certainly other options.
I tried installing WebSphere portal ten years ago for some reason and that killed my laptop. I'd say that that's probably the best possible outcome...
Oh, and I think TAM/TFIM/ISAM might be ok for companies over a certain size.
Not sure about their cloud offerings. Probably not promising.
They tack the name 'Watson' on a lot of stuff, but some of that might be good.