You could always drop the MoT on the Prince and field him undivided - I know it's a way of getting his 4++ save, but it's not really needed, and those 20 points can be spend better elsewhere. For instance, upgrading to Possession on the Vindicator (which will have every anti-tank gun pointed at it as soon as it appears).
It's a reasonable list overall, but I'm not sure you really have any way of concentrating your force - the units are good in their own right, but I just don't see how they'll work together. For instance, if the Chosen are infiltrated close, they don't have any reliable support - maybe the daemons if you choose to bring them in there, but otherwise nothing. The Prince is speedy and good, but he has no backup. The 10-man squads are shooty, and perhaps that's how you could focus the list, but then it's hard to move and grab objectives, and they're not great at it. Everything is a reasonable choice, it just doesn't come together, I think. I'd need to spend time thinking about it to figure out a better solution using what you've listed and the options.
One option - drop the Vindicator entirely and one Obliterator, to take a unit of 8 Havocs with missile launchers. Give the 10-man squads two plasma guns and Champions with powerfists, and perhaps make the Chosen 4-melta and a powerfist or something. The anti-tank weapons of your opponent then don't have a target, the 10-man squads can advance and fire if need be and are capable in close combat, and the chosen infiltrate with the intent of taking out armor. The daemons can support them, and the Prince makes a counter-charger. The one oblit drops to take out tanks, or finds cover somewhere and snipes. It's still not the best - I feel the Chosen will still feel unsupported most of the time, particularly if the Daemons don't come in, but I think it'd be an upgrade.
