To be honest, you have more than enough for a 10 gallon tank. I suggest cleaning the glass yourself if that's what's bothering you, the reason being those critters increase the tank bioload with questionable overall benefit
There is a myth going round that you need to add fantastic numbers of hermits, snails etc to tanks (e.g. for larger tanks, in the hundreds for each critter). A myth in all likelihood propagated by those wanting to sell them...