Between constitution and tradition which is more important.
I would go with constitution.
As reported, Tengku Razaleigh said, ""This handover thing is unconstitutional and it is not something that should be passed down from one leader to another. The matter of Umno's presidency and in turn, Malaysia's prime ministership, should be endorsed by the grassroots,"".
I agree with him.
Constitution is something you don't play with and/or take lightly of it. To a certain extent going against the constitution is as good as going against the law.
Tradition on the other hand is something which you have been doing for a long in and within your group and/or clan and/or community. Going against the tradition is just going against your group's and/or clan's and/or community's beliefs and have nothing to do with the majority.
Tengku Razaleigh, you are probably the only good one left in Umno and don't think it's adviseable for you to stay in Umno and change them from within as Umno is beyond any repairs, do leave Umno and join/start another political party. You can perhaps make better changes in that way. You left Umno one and you can leave them again. There are just too many corcodiles in Umno, they will probably chew and digest you even without you knowing it.