Slight change to AG Chocolate Milk Stout

Hi, I am doing a AG kit in the morning and have a few extra types of grains on hand. Looking to add a bit to the kit. I loved this brew the last time, but would love to add either a bit more chocolate or milkyness to the end taste. Not a technical kind of guy and have just started looking at all the different ways to make little changes.

The current grain recipe is:
– 8 lbs Rahr Pale Ale Malt
– 0.75 lbs. Fawcett Pale Chocolate Malt
– 0.25 lbs. English Extra Dark Crystal
– 0.75 lbs. Weyermann Dehusked CaraFa III

I have the following on hand, they are a bit old but figured no harm would come from adding if someone says I would benefit. I have:
–0.5 lbs Simpsons CaraMalt
–0.5 lbs Briess Caramel 60
–0.5 lbs Briess Caramel 90
–1.0 lb Fawcett pale Chocolate

Also, I batch sparge. Read by increasing the grain would help with the overall efficiency. I ended up getting an extra 4oz of chocolate nibs this time also. Read some people put in a little to the end of the boil and other just add a bit more to the secondary; recipe calls for 4 oz to the secondary. Thanks.

I ended up adding 0.5 lbs Simpsons CaraMalt & 1.0 lb Fawcett pale Chocolate to the grain recipe. Just starting to try to understand the different grains and what the will do. I had a first batch gravity reading of 1.053 (5.5 gal) and second batch was 1.045 (1.25 gal). Boiled down to 5.5 gal and had a 1.061 (adjusted for 72 degr) OG reading when I pitched the yeast. It is very black and a strong burnt coffee flavor. I think it will turn out pretty good. I used a SAFALE S-04 yeast.