I've just checked some charts. Most altUSD pairs seem to be at resistance here on weekly, so it's not a bad place to book some profits. But on BTC's next leg down (the one to 7.7k maybe?), alts could be worth investing in (mid term), at the expense of BTC. including IOTA and QTUM, have good mid term potential it they don't break support on BTC's drop.
But considering how slow BTC is these days and how dominance is correcting, alts shouldn't be hit as much as in March on the leg down. Still, it's not an area to buy but to book profits now. Unless there's a convincing breakout...