The google page rank is not that important but may be important in some cases, especially in highly competitive websites (e.g., ads site, real estate).
For me, in most cases, in-page SEO is sufficient.
The number of visit is sometimes not even important, what is important if you get the visitors who will actually do what you want with the website, like would they buy, or would they avail your service, etc.
For example, I have a client who owns a drugstore chain and is looking for drugstore franchisees. I optimized the site for keywords "drugstore franchise Philippines" (I'm based in the Philippines, and so does the client). Optimizing for keywords "franchising opportunity" would definitely yield a high traffic, but most of them are undecided; they are looking for business but is not yet sure what type of business. Optimizing for "drugstore franchise" would get more visitors from outside the Philippines, still it's more traffic. However, my client does not offer the franchising opportunity outside the Philippines. Hence, with they keywords that I chose to be the basis of optimization, the client would definitely get the intended audience, those who want a drugstore business and is based in the Philippines.
I have another client who brokers with commercial spaces. Unfortunately, real estate is a very competitive sector and as such, I cannot bring that website on top for keywords "commercial space Philippines". Hence, I am currently exploring how Google PR works and eventually increase that website's Google PR.