Advice on static allocation

Recently I’ve been trying to develop a passive & static portfolio for my PA, where I could just DCA and let the portfolio grow over time (with dividends reinvested). Ideally, I’ve been trying to achieve a portfolio with S&P 500 like returns, but at lower drawdowns & does not lag like 60/40 under stagflationary environments. So far I’ve come up with the following portfolio: 25% QLD (2x QQQ etf. Main thesis is that innovation is always going to drive returns in markets long run and the NASDAQ will capture that. The historical sharpe & sortino for QQQ tends to be higher than SPY while the historical sharpe & sortino for QLD is about the same as SPY) 25% IEF (medium term, 5-7Y treasuries that works well during recessions where the fed typically drop rates & duration comes into play. Used IEF instead of TLT given that the duration sensitivity of TLT hurts the portfolio too much during stagflationary periods.). 25% GLD (gold is generally stable and the chart shows long run steady price appreciation. Mostly there due to diversification benefits as the returns are lackluster with no dividends. The fact that it tends to have positive runs during volatile market environments is also another factor) 25% UUP (dollar etf that benefits from rising rates, which IEF suffers from. Has a high dividend yield of 6% rn and low correlation with all other assets). The general idea behind this portfolio is to let QLD drive returns, reducing the portfolio risk via diversification into low correlation assets that have steady long run price appreciation & exposures that do well under different macro environments (correlation matrix shows 0-37% correlation between all assets). That way the sharpe would be boosted & drawdowns minimized. My only gripe is actually the volatility drag & high expense fees of the leveraged etfs, which reduces the sharpe compared to its non levered counterparts. I did some back testing on testfolio (with monthly contributions & annual rebalancing), where the results are surprisingly good from 2007 to present compared to 100% SPY or 60% SPY and 40% TLT. Any advice on how this portfolio could be further enhanced?