Research by Brinson, Hood and Beebower (1986, replicated many times since) found that 90%+ of the variation in a long-term portfolio's returns is explained by asset allocation, not by security selection or market timing. In other words, your stock-versus-bond split matters far more than which specific Swiss large-cap you picked.
Classic frameworks include the 60/40 portfolio (60% equities, 40% bonds), the all-weather portfolio (Ray Dalio: 30% equities, 55% bonds, 15% commodities and gold), and the age-based glide path used in pension funds and target-date funds (equity weight = 100 − age, or 110 − age for longer horizons).
Real-life asset allocation must reflect your total balance sheet: pillar 2 pension assets behave like fixed income, owning your own home is concentrated real-estate exposure, and stable employment income is similar to holding a giant inflation-linked bond. Build the brokerage portfolio to complete the picture, not to mirror it.
A 35-year-old Swiss professional with CHF 80,000 in pillar 2 (behaving like bonds) and CHF 50,000 in brokerage targets 70% global equities. He puts the full CHF 50,000 brokerage into a global equity ETF — combined with pillar 2, his total financial portfolio is 38% equities/62% bonds, which is below target so he raises his monthly ETF contribution.