I have done similar things to moderate the ECL adjustment.
For instance we have a Drow mute mime Bard. I granted a ECL adjustment for the mute nature (especially for a bard). I also had a set of enhancements for characters at the time of character creation. One of those enhancements was a free ECL adjument of 1. Other enhancments were free ability adjustments, family inheritance minor magical items, amongst other things.
If you feel the need to grant something for the ECL challenged player, you should give some sort of minor boost to the other players... and the best types of boosts are focused more on the role-play aspect than on the mechanical aspects. For instance, they might be the 'owners' of a small fortified building out on the plains - but as they arrive to take possession, they find it occupied by _______ (foes, monsters, rivals, squatters, or other family members who claim it is theirs by right). They get the feeling of getting something, but it is really just part of the campaign - and you get to justify the ECL adjusted character.