Contacts is much the same. Select a group (which can be all of your contacts) and export it as a vCard. Then import the group into the account you're going to hold onto.
Notes are trickier but not impossible. Writeapp's free Notes Exporter lets you export notes as plain text files.
With all the housekeeping done, start your bold new life of using only the keeper account. To help make that possible, after ensuring any data associated with it has been archived and synced with the new account, remove the unwanted ID from your devices.
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