Welcome to Experimental Heavy Lift
Big Rockets....
Economic....nope.
Practical...not really.
Dangerous...only for adjacent suburbs.
Big ...yes.
"BFRs that were BFRs before the BFR was a BFR."
TsSKB Progress Methane Proposal 2013
180t to LEO, 3500t, 90m, 4m boosters, 8m core
RD-0164 is the proposed 3300kN methane engine (sl Raptor-equivalent) for Soyuz-5
boosters are crossfeed
http://www.russianspaceweb.com/stk.html