You've got ten letters with diacritics which doesn't strike me as excessive. I suppose the six different types of diacritics is on the high side, but I don't think it matters. Any language you create is bound to be unusual in some way or else it would be kind of pointless. If you want to see serious diacritic action, look at Vͯ̊̑ͤ̃̓̇̓͑ͭ͋̋͌̉̇ͯí͋̀͗͒e̒̃̀ͦ́t̄̄̓ͩ̆̊͆̇͌̾̋̐̉́̔̍ͩn͂̈́͌̈́͊̽̚ā͒̽̍̎ͤ͗̏ͪ̽͒̂̎͌ͥm̾ͫ̋͛ͮ̈̆ͤ̓͂̓eͩͦͫ͆̂̇̆̏ͧͤs͗ͬ̋̒̿̈́̃̆ͧ̒͒̊e̋͊ͪ͂̒ͣ͆ͭ͐ͫͪ̈ͩ̓̒̌̋̚!