I don't know what you mean by conservative to moderate regarding equity funds. Equity funds are by definition neither conservative nor moderate.
Both Scott Burns Lazy portfolios and Bill Schultheis' Coffeehouse Portfolios use
(US-IDX) Vanguard US Total Stock Index (VTSMX - 0.18% expense ratio)
(INT'L- IDX)Vanguard Total International Equities Index (VGTSX - 0.27% expense ratio)
Andrew Tobias also uses those in his Index portfolio mix(es).