Should Captains be punished more for slow over-rate?

hi friends.just wondering. if any stat geek out there,let me know which captain was asked to sit out the most because of slow over rate in previous matches. let me recall.Dhoni was rested during on the series earlier because he bowled the overs slow and twice this tour,he did the same mistake again. the umpires fines 40% of his match fee (negligible comparing his ads and IPL revenue ) and one match ban but he is intent on doing it again and again. so should umpires look other means to punish captains rather than fines and match ban? because this one doesn't seams to work