The "team" ethic works to a point, but as we found you also need to add better quality, if you want to keep progressing. As you know we struggled for the first half of the season even with a close knit group, who had won the double the previous season, due to not recruiting successfully in the summer; and it wasn't until we added to the quality without diminishing the "team ethic" that we progressed.
Watford and Wimbledon famously in the past progressed from the basement to the top flight, basing it on team work, but of the team that made it to the top only one or two of those original players survived. They managed to add quality at each level, without losing the team ethic.