There definitely are some pretty crucial DLCs, though. Like, good luck playing Skaven without ratling guns/jezzails or HElves without SoV. Of course it's not so bad that you'll be left with absolutely no archers or monsters with any faction if you don't get any DLCs, but the difference between having and not having many DLC units is not insignificant. Especially the 4 release factions are extremely barebones with no DLCs. FLCs alone don't cut it.