That you suggest all 3 as possible solutions for multipurpose theme like Avada seems to be at odds with their being multipurpose products pitched to non-technical users. Paying for dedicated WordPress hosting or configuring caching plugins are unlikely to be at the forefront of their mind when they make the initial purchase. Can you see that disconnect?
Robert said he did an average of 4-6 of these gigs per year for a while depending on his schedule and the work involved. The best part is, he charged a flat rate that usually worked out to around $100 per hour. And remember, this was pay he was earning to advise people on the best ways to use social media tools like Facebook and Pinterest to grow their brands.
I thought I would just bring something else to your attention; I did take a second to look at your site; you know why I left within just one second? EXACTLY! You have less then 3 seconds to make your first impression on visitors; if your visitors are bouncing off your site at the speed of light, they either found your site by mistake, or they were not impressed with your site, and left, which means? right, they did not trust your site!!! What happens if you have a high bounce rate? right, you can certainly lose rankings! Is google going to keep sending you traffic if you have nothing to offer? nope! I can not say this is your problem, or you could have multiple problems going on at the same time to cause you to lose rankings. I can tell you one thing for sure by just taking a 1 minute look at your link profile; You have quite a few links, and you have almost no authority, what does this mean? This most likely means you are spamming your link to poor quality sites. You also have a massive amount of do-follow links which does not look natural vs your no follow links, and with your site having low trust flow, do you think your site deserves that many do-follow links? I wonder what google thinks? at first glance, your anchor/link diversity does not look to bad, so your anchor/text does not look over-optimized, but whoever is building links for you, consider firing them immediately, as you are getting all the wrong links. I am going to assume at this point google has certainly given you a penalty; Your next move to to hire someone to audit your site, and start disavowing/removing bad links from your portfolio, over time, your rankings may come back, and that may depend on other factors also, but at this point, it certainly looks like you have link issues. Just a little bitty research goes a long way. good luck.