Way, way too complex IMO. Just have 100 times (or some other multiplier) of current expenses (fixed and reasonable "fun" factor) and forget about it. Get there with fixed return assets (Insured CD's) and you do not even have to "watch the equity market" just the interest rate market a couple of times a year to coincide with known maturity dates. Helpful to have a couple of good Government Annuities and paid Medical care.
Watching equities is like painting a moving train - way too hard for me.
Vietnam Veteran, CW4 USA, Retired 1979