[Babs]

Your build is very similar to mine and I will be ordering in April or May also. I had the same issue with Mocha Dakota and Sport package. To get MC seats, you will have to select Mocha Nappa instead and this adds the Mocha Interior Design package for $1950. I was at a dealership yesterday to look at the Mocha Nappa interior on a 50i M Sport. The leather looks really nice and the stitching on the seats looks nice in person. I am not really a fan of the leather dash but it looks good too. The only gripe I have about the interior is the black plastic looking panel that sits just below the wood (or aluminum) trim in the dash, which is more pronounced and visible on the front passenger side.
I personally think that Space Gray would go well with either Mocha or Black interior. I don't like black, so Mocha Nappa will be my choice. I haven't seen the Terra Dakota on the X5, but it seems to have too much of an orange hue for me to even consider it as an option.

The only thing I will pull from your build is the Enhanced USB and Bluetooth plus Smartphone Integration - $500. Opasha (a great forum member here) has confirmed that this can be coded and allows you to have more space in that compartment. So, skip this one.

Below is my build
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BASE MSRP - $56,200
M Sport - $4,500
Space Gray Metallic - $550
Mocha Nappa Leather - $0
Fineline Oak Wood Trim - $0
Cold Weather Package - $550
Driver Assistance Plus - $1,900
Driver Assistance Package - $1,400
Dynamic Handling Package - $3,600
Lighting Package - $1,900
Adaptive M Suspension - $900
Multi-contour seats - $950
Mocha Interior Design Package - $1,950
Premium Package - $2,550
Rear manual side window shades - $250
Harman Kardon surround sound system - $875
Space-saver spare - $150
Destination & Handling: $950

Total MSRP as Built - $77,275
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I plan to have some mods done once I get the car:
1. The kidney grills will go to black
2. The stock wheels will go to 22 inch staggered with custom paint
3. RaceChip Ultimate will be installed
4. There will be splitters in the front lower grills,
5. 6WB Digital instrument cluster will be installed to replace 6WA
6. Carbon tint of the front windows
7. Coding for the car with the help of Opasha

All the best with your order and keep us posted on your final decision. I will keep everyone updated on my build as well.

Very shortly, you will get additional opinions from more experienced forum members.