Sort of. A lot will depend on player skill the boxes are pretty straight forward in terms of composition. Deathwatch, Wolves, and Tau in my opinion have the best options.
The real value in the kits is the terrain.
The best way to get into killteam is to look at the faction lists and see what options you like and if your choosen factions start collecting box has those options or a majority of thise options. I built my necron team out of the start collecting and a death mark box. $120 got me everything I wanted. Some like deathwatch, harlies and tau will be able to do a good team for just a box.
Maybe something like elite games get an increased point limit but a minimum and maximum number of elite units that must be fielded, to keep the number of models on the field manageable, with custodes only playable in elite games.