Those look good to me.
Anything else it needs mechanically aside from the anti-dragon statblock? Looking back at other templates, we don't usually include tactics, but I will give a description of the ability array used. I guess the other question is if we want to improve the equipment and give it other magic items. I say yes! We probably ought to give it some other weapons (to take advantage of TWF when unarmored).
We'd better figure out its equipment. Do we use its character level of 13 to figure out its wealth or its CR of 14? The former gives us a budget of 35,000 gp and the latter 45,000 gp.
I'm thinking you normally use CR to determine wealth, which'll give us an extra 10k to play around with.
We're still using the greatsword primary weapon version, right? So my previous proposal for a
+1 dragon bane greatsword (8,350 gp) and
+1 composite longbow [+5 Str] (2,900 gp) as the main weapons seems a good start.
We're taking the "full plate" option. That's 1,500 gp. We might as well masterwork it for another 150 gp and it should be at least +1, for a total of 2,650 gp.
That's 13,900 gp, so we've still got plenty left from our 45,000 gp budget - 31,100 gp.
We could go for adamantine (+14,850), mithral (+8,850) or plain +3 (+9,000) armour, for example, and still have 15-20k left to improve the weapons or buy a few miscellaneous items.
Hey, I just noticed that my last update didn't take. I'll do that with the spells and equipment.
Yes, this board does that to me sometimes too.