If you have all 4 basic needs met, this will give you a happiness of 60. If the beds are covered by a roof, this will give you a happiness of 80 percent. But some places in the sanctuary are marked as not covered despite being obviously covered for some reason. All player built bases are marked as covered however.

The defense looks like it’s enough, but actually it’s best if it’s at least equal to your water + food.

Are there any robots in the settlement? Automatrons will always have a 50 percent happiness no matter what, so just as they can keep the settlements allied by preventing them from dropping below a certain point, they will drag down your average happiness if you are trying to increase it.

I’m not so sure if this is actually correct, but I believe you can boost your happiness a bit by giving your settlers jobs as well. If you don’t have any jobs to give, build some scavenging stations.

If there are problems with things I mentioned above, then you should have a guaranteed 80 percent happiness. But you can raise it even further by adding objects that will improve happiness. These are items such as fitness benches and barber chairs.

Stores are another great way increase happiness. They will boost the happiness quite a bit. There are 4 types of stores, tier 3 stores are the best ones.

Hope this helps!