Macking a custom soundboard, what features should I include, placement of connections

[Ben StarKiller]

I'm a hobby PCB designer and want to build my own soundboard. Partially because they are so expensive and partially because I want to use RGBW LED's in sabers I would build. Most sound boards I see usually control only RGB or 3x channels and require extra work to get that 4th channel. I want to base mine off of running the CREE XM-L Color LEDs.
I will adapt open source soundboard code from FX-SaberOS, USaber, LightSaberOS, TeesnySaberOS. For testing I purchased a $8 mini flight controller which includes a STM32F303(72MHz 32-bit MCU with I2C,SPI,I2S), MPU6500, 5V buck-boost so it can work on either 4.2v or 8.4v and 6x 10A MOSFETs. It is only missing an SDcard and amp which can be done with a DFplayer for proof of concept then add something like the MAX98357A and SPI flash(16-32MB) or SDcard later. Ultimately I plan on using the STM32F072(MCU), LSM6DS3(IMU), MAX98357A(DAC-AMP), 6x 6-10A MOSFET or 4x LED2001 or LT3476, TP5100(charger), LTC3111(5v buck/boost), 3.3v 500mA-1A LDO.

What am I hoping from posting this is anyone seeing features that I am missing as well as getting feedback on the best placement for the wire connections.

Attempted features:

• 1 or 2 cell operation with 5v buck-boost voltage regulator(4.2-8.4v)
• 1 or 2 cell battery charger (set with soldering jumpers, could be set automatically but adds to components and idle power draw, or could be set through programming)
• 3.3v LDO for MCU, ICs, GPIO
• Accelerometer/Gyroscope
• 16/32MB SPI Flash on-board or microSD card
• 6x 6A+ MOSFETs or 4-channel LED driver 1.5A per(channels can be used for RGB-W, strip, LED Crystal, cross-blade)
• NeoPixel Compatible
• I2S audio out to an I2S Class-D 3W AMP for best audio sound (44.1kHz/16-bit/WAV/Mono)
• 2x buttons (Main, Aux, expandable to more depending on other features used)
• Momentary or latching switch compatible through software
• RGB status light - current resistors on-board (I plan to use switches with an RGB for status; on(same color as blade)/charging/charging complete/more+)
• 2x Aux GPIO for LEDs or buttons
• I2S audio out to an I2S Class-D 3W AMP for best audio sound (44.1kHz/16-bit/WAV/Mono)
• 20.3mm wide for largest compatibility in chassis

Placement

• LED +/- (right)
• Batt +/- (left)
• Charge +/- (left)
• Speaker +/- (left)
• buttons/status led/Neopixel (bottom)
• microUSB (best fit)
• SDcard (left/underside)

Questions?
Should I use Cheaper MOSFETs or full on LED drivers? (LED drivers would be the most efficient and wouldn't require resistors at all, large inductors would increase the size and cost)
If I use MOSFETs should I make space for 2512 resistors on-board(would need to limit it to 4)?
Do enough people use PLI (power level indicator) to add native support? (Would mean picking a 64-pin MCU rather than the currently picked 48pin)
Missing features?

ObiSaber.jpg