Two sample Kolmogorov-Smirnov test and p-value interpretation

I have a question regarding the interpretation of resulting p-values of a two sample Kolmogorov Smirnov test.

Basis of my analysis is to try to identify groups that show a difference in their distribution difference compared to totality. I used a two sample Kologorov Smirnov Test in R to do so.

Sample sizes:

Full = 2409
Group_1 = 25
Group_2 = 26
Group_3 = 33
Group_4 = 43


Dataset plots:

"Other" contains a collection of groups containing less than 20 datapoints.

The resulting p-values I get when I compare each "Group" against "Full - Group" are the following:

Group 1: 2.6155e-002
Group 2: 2.1126e-003
Group 3: 7.2113e-002
Group 4: 7.3466e-003


How can I interpret these results - especially with regards to the low number of datapoints per group as well as the difference in sample size for Full (N=2409) and Groups (N=25-43)?

Is the choice of a KS test good or might another test be more appropriate in this case?