Merge account type and account kind
I saw that Odoo has done this merge by simply put the account kind to the account type.
At first sight, it seems to work except for the view kind but this could be fixed if we consider account without type as a view.
The main advantage I see is that accountant understand the account type but not always the account kind as it is something specific to Tryton. So if kind is defined on the type, the account will not have to care about as creating account can happen often but creating type is much more rare.