The pose_follower is a local planner that implements the BaseLocalPlanner interface and tries to follow a given plan (AFAIK with orientation per waypoint) as closely as possible. It will only follow a given plan and not modify it, so if you have sparse waypoints the tracking might not look smooth (then you would have to first generate a smoothed trajectory in a preceding step). It might has to be modified to work well with a Ackermann-steered vehicle, however.
If you really want to plan for a Ackermann-Steering vehicle I can recommend looking into the SBPL lattice planner. It uses lattice (motion primitive) based plans and thus also can plan for Ackermann steering vehicles. The existing ROS package is not able to consider multiple waypoints though, so you'd have to write code yourself that creates a plan between two of your waypoints and then concatenates those small plans into a single large one. Note that this solution provides obstacle avoidance capabilities.
If you do not want to consider obstacles, you could probably implement spline/bezier curver interpolation yourself, I'm not sure there is a package available that does this.