I might be misinterpreting your question, so here are two answers:
If you're wondering how to get the delay effect to repeat more times, increase the feedback parameter.
If you're wondering how to adjust the wet/dry mix of a particular effect block (such as delay or pitch shift), I would suggest you use one of the mixer blocks. One input should be the same as the input to the effect you're mixing, and the other should be the output of that effect. Then adjust the Level A and Level B parameters of the mixer block to achieve the levels you want.
Hope this helps!
Yes I was talking about the mix of the delay not the feedback. I was expecting a mix knob in the delay and pitch block itself. Like almost all plugins and hardware have. Seems more fast and practical to me than having to put a mixer block in the there.