Ohhh, this is my fav meal - along with roast pork - we love roasts in my family, usually my mum does a roast every sunday night, three of us go & my brother & SIL, we all live in the same town.) but since not working - i worked every second weekend - now we take them in turns!

Mine is pretty much same a Caro's but -

I put the oven on 180 fan forced, i put about a cup of water in my baking dish (my mum & SIL use oven bags)
I cut my vegies around the same size, these i put in their own dish & brush them with oil, i put these and my roast in at the same time and cook them for about 3 hours (i always have fairly big roasts - big family) 3 hours i know my vegies are ready
(had a ***** of a time with this part!!)
I also use the greens gravy - but i cheat and just use a gravy boat with boiling water.
HTH!!
Good luck, nothing like cooking for more people!