I have seen a recent spike in the number of nodes that support bigger blocks (2mb) with Bitcoin Classic.
So? It is relatively easy to jump-start a high number of nodes, especially if you have capital. There was even a recent analysis that shows that a maximum of 213 people are behind 800 nodes. Additionally, it is worth mentioning that they're promoting their Sybil attack by stacking datacenter nodes.I was wondering which would be better to support, since I have doubts on whenever bigger blocks could cause an issue to BTC's decentralization.
They will have an effect on it as it will increase the requirements for node operators. The question is whether the loss in decentralization is going to be negligible or it is going to be a bit more significant.If it were me, I think I would go with Classic, since bigger blocks means more capacity for transactions. I would like to view your opinion about this. 
The main reason for someone to rush for more transactions is greed (i.e. hoping that: more people -> higher price). When scaling Bitcoin one has to be pretty conservative or else it might run into huge problems. Additionally, Core is coming up with Segwit which will also increase the capacity.i'm not a classic or core supporter anymore i support Unlimited. 
That's even worse.