Cost per Action is the way forward. You stop paying per click, and instead you pay per result (a sale, a registration, or whatever you define as a 'result'). It takes a month or two to get going, and you need to start with one of the other payment options available. But in the end, you will be able to have an advertising campaign that you only pay when you have the performance and results you desire. And grow it to the scale that you wish.
Display advertising is a super way of getting highly targeted traffic but needs to be set - up correctly to perform either as a stand-alone channel or as a complement to your search advertising campaigns. Depending on your needs, I may recommend different settings for your display campaigns
Remarketing is when you order your ads to chase their past viewers as they browse across the Web. This is a very effective way to increase your brand awareness and start new relationships with your visitors. I can set up remarketing for your ads and place it on auto-pilot (dynamic remarketing) and use it both on display and search advertising.