Playing with track Weight may allow quick solving convergence, while keeping some poor quality tracks.

Run this script into a python console, and then solve for camera motion, repeat until the Solve error stop to lower.

    for clip in bpy.data.movieclips:
        error = 0.5 * clip.tracking.reconstruction.average_error
        for track in clip.tracking.tracks:
            track_error_weighted = track.weight * track.average_error
            if  track_error_weighted > error:
                track.weight = error/(track.average_error/track.weight)