There aren't any good reason to ramp up diplomatic tensions by expelling more staff than is neccessary by the rule of reciprocal action.
Note that Russia expelled twenty operatives in retaliation to the Czech republic's expulsion of twenty Russian intelligence officers.
This kind of action is very well understood in diplomatic circles and works to ratchet ...
As others pointed out in the comments, a list of successes would not be published by all concerned agencies.
There is one example from Cologne, Germany. were information from the NSA was apprarently passed to German authorities. The German wikipedia text says so, as did news media and spokespeople at the time; the English one is shorter.