As @mindeswx pointed out (I guess) it really depends on your cost of driving that traffic. If it is via Instagram “automation”, I would aim for at least an EPC of 0.15$ considering the costs of running an account and recent limitations.
General speaking only you can judge if your time is better invested into improving the earnings for the existing traffic or increase the amount of traffic. Both has valid reasons: improving revenue on the existing volume of traffic gives your niche/operation more survivability for future platform changes while on the other hand scaling the traffic will give your more investment opportunities either in your existing niche/operation or in new ones.
For landing page optimization I always recommend making the user as committed as possible. Make sure they are emotional and time-wise invested before you present them the “bad news”, this will really help to improve your conversions on the existing landing pages. If you want to optimize multi-step landing pages - which I highly recommend for the conversion ratio - I can recommend mixpanel (https://mixpanel.com/) for figuring out when you lose the users. This way you can optimize the multi-step flow and put elements with a high exit ratio to the end of the chain (removing them or optimizing them might also work).
