I think it is more accurate to refer to "wrong concentration" rather than "too much concentration" because right concentration is a factor of the path. Wrong concentration is pushing the mind with too much effort/craving. Where as right concentration is lead by right understanding (per MN 117).
Is like have some rocks near a cliff that need to be disposed of. Wrong concentration & wrong effort are taking a hammer & smashing up the rocks. Its hard work. Where as right effort is simply pushing the rocks off the cliff and right concentration is watching the rocks fall off the cliff.
Right effort is the effort to let go, which arises from right understanding of & faith in the four noble truths, which explain letting go is the way to end suffering. Right concentration is the clear stable aware mind arising from letting go. Of course, there must be the constant mindfulness (non-forgetfulness) to engage this path of letting go.
This is how the five faculties interact in noble path meditation. SN 48.10 states:
The noble practitioner develops concentration & attains jhana by making letting go (vossagga) the meditation object.