$Invesco QQQ(QQQ)$
I wouldn't go for either of those though. I'd personally recommend a value lean (SCHD $Schwab US Dividend Equity ETF(SCHD)$ sort of accidentally provides that) and a small cap lean. Something like VBR $Vanguard Small-Cap Value ETF(VBR)$ or AVUV $Avantis U.S. Small Cap Value ETF(AVUV)$ to combine with your VOO $Vanguard S&P 500 ETF(VOO)$ .
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