So I have just done a play through using both npc mods and there are some things to be aware of.

1. KEE see week one bandits as zombies and WILL attack them on sight. This may cause a lot of lag, and a lot of police/paramedic spawning to clear up the mess, while also probably getting attacked too creating a massive cycle of emergency service spawns.

2. Lower KEE spawns to about 250, lower Week one interior, exterior and military spawns to 2.0

3. in the 16 bandit spawn options, Try to set all of them to start spawning AFTER 7 days so the week one cycle finishes (Week one already has its own bandits within the 7 day period) set everything to wanderer, and have a spawn chance of 0.9
if you want preppers, set them to guard, and set any bandit factions to thief. set all weapon magazines to 2 so you dont end up maxing out on unlimited ammo.

4. If you feel that it is slowing your gameplay down too much, either deactivate KEE mod until after day 7, or do not enable KEE at all until after the week one cycle has finished.

5. If you do take on KEE survivors into your group, keep them at home to guard your house, (if armed, they are VERY effective) do not bring home any week one npcs to your house because KEE companions will kill them. Only bring KEE companions out with you after the week one cycle has finished, because if you havent worked it out yet, they go full psycho on anything week one related.

Both mods can work well together but you need to make sure the settings reflect that you are going to have a very highly populated game before zombies even turn up, and any npcs you kill, will rise into zombies on day 7 so try not to make it too hard for yourself and overwhelm your playthrough and your pc.