I think it would be nice if MultiBit HD allowed you to specify a single full node (out of the 8) as a hint. Specifically I'm thinking of circumstances where someone is running a full node on the same host or local LAN, and would like to make use of it.
To a small extent, it could encourage people who are already somewhat interested in running a full node towards doing so (and conversely, not having such an option may encourage people to stop running a full node after upgrading to MultiBit HD from Classic). I think (gentle) encouragement such as this would be a good thing.
Alternatively, an option that calls peerGroup.setUseLocalhostPeerWhenPossible(true) would be almost as good IMO.
connections to other nodes.
That is to other Core nodes, Electrum (which is SPV), MultiBit, the Schildbach Wallet.
I'm off-topic here... but Electrum connects only to somewhat-centralized servers; it doesn't participate in the P2P network (it does do SPV on what it downloads, though).