by the way spain is actually can be your friend
think about it base value of seville trade node is LITERALLY NOTHING
so... he colonizes with you and pulls all good stuff to thereThats why I hate annexing portugal as spain for same reason let him help you colonize new world to incrase value of your poor trade node! if you annex him you lose 3 coloniser at total!
I usually aim to PU/vassalise some other colonisers for this exact reason. Especially now that CNs have un-nerfed colonists you can really just set a snowball and give it a gentle nudge down the hill. Then you can focus your own attention on colonising and conquering into Trade Company zones in Africa/India/Spice Islands.