With 1600 downloads/day you are in the "Fly Stage" (see our growth stages categorization: https://www.slideshare.net/christianpuricelli/mobile-app-marketing-presentation-81456295). To growth from there ASO, PR, App Review websites will not help you any more to growth significantly. At this point you could try to reinvest the cash flow you are generating for paid acquisition, an influencer campaign. Also at this point it makes sense to start optimizing all conversions.