I would not.
I would especially not support a sequel in a series that's been going downhill for years. And no, I don't care that it's not their fault - once it starts going down it's a sign that they should get what they learned from it and move on to something fresh that, due to the experience of its creators and the fact that it'd be liberated from the need to make up for any bad moments, live up to any good moments and to generally be directly compared with previous works, could potentially be even better. (And yes, I liked Risen a lot -the 1st, I haven't played the 2nd yet-, though it was certainly far from the most ideal example of doing something different.)
I would also not fund any more games that attempt to recreate older glories. Crowdfunding provides a great opportunity for developers to unleash their creativity and show us their true abilities by taking risks, exploring outside their safety zone and pushing the medium forward without restraints and without facing dire consequences for even trying. If they intent not to take risks and play it safe by repeating what has worked well in the past for them then I will not take any risks either, I will play it safe and repeat what has worked well in the past for me: wait for reviews and price drops.
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Also what Lucky Day said.