I'm upgrading to 120, am I on the right track?

[NYIntensity]

Hi all, I'm beginning the process to upgrading my 55 to a 120, and here's where I'm at. In a week or two I'll be buying some second hand equipment from another RC member who's selling his 120. My tank right now has:

(1) H. Malu or H. Aurora (recuperating from a sickly tank from my neighbor, will know once it grows a bit)
(1) BTA
(1) Pair GSM Clowns
(2) Azure Damsels
(1) Zebra Damsel
(1) Emerald crab
(1) Acan frag with approx 16 heads
(1) Frogspawn coral, about 6"x3"
(1) Unidentified 1/2" clam (yes, it's tiny right now, but persistent)
~30# live rock, 40# base rock with coralline growing sparsely but fairly consistently.

The proposed 120# tank will be 48x24x24. The equipment will be:
Hamilton 2X 175W MH with 2X 110W VHO Actinic bulbs
Large CPR Hang on Refugium with Pump
T-5 fixture for Refugium (24”)
E.T.S.S. Protien Skimmer with Pump
Gen-x PCX 40
Koralia #3 and #4
dual wave maker
ProHeat 500W titanium heater with external controller
Sea Swirl

My questions:
1: This tank will be custom and acrylic; I plan on going with euro bracing, but where do you suggest my overflow(s) is(are) located?

2: What direction would YOU take this tank? I haven't really decided on whether I want to be SPS or LPS dominant, or how I want to set the tank up.