My guess is as soon as you post a new hub your traffic will be high because these are repeat visitors, search engines and some followers. The next day on it is the new visitors. They are very hard to get. You need to have a very wide set of followers and a big base. Then they can be steady. You need to keep posting a new hub often to of course get links and also keep posting the new hubs. Dips cannot be eliminated completely by anyone. I also think the informative hubs get more steady traffic and have a long life because of the wider base of readers they have. Specialized topics target narrow groups and have shorter life. If at present you have all content with narrow target you should create a mix if your major concern is traffic. Otherwise just don't worry about dips.Stay focused and keep the continuity. .