Getting more specific with parts

So I knew I wanted this calculator to be powered by a MediaTek MT6580, but the easiest way to do that is with a predesigned board some Chinese OEM is already making. That was what I was looking at earlier, but for the keyboard and charging to work like I wanted, I'd need one with 2 USB ports, which that one didn't have. I recalled there was one shown in a welcome phone in an old SMOOREZ video, but after a lot of googling, I couldn't find it for sale anywhere. After a bit more research (aka watching lots of videos that might have some useful info), I realised the phone with 2 USB ports was probably a very old one that wouldn't do everything I wanted. I've decided that the best thing to do from here would probably be redesigning the keeb to have a passthrough for charging the phone like a Clicks keyboard and using the board from a Moxee MH-T6000, as it's too unbranded to be that hard to modify probably (I give you all permission to bully me for this if I'm wrong). I'll probably also redesign the keyboards to be swappable and also make another keyboard design for left handed people because I'm slighly more ambidextrous than I am concerned about my mental well-being.

Image of the phone I'll be parting out:

Designing the keyboard & suffering with PCBs

First, I followed along with the Hackpad tutorial to learn how to make a keyboard in KiCAD. Then, I realised the keys with that would be way too big for a calculator keypad so I started over. I discovered the Tanmatsu project already had a keyboard that could be easily modified to suit my needs, so I modified that into something that'd work. Then I realised I had COMPLETELY no idea what I was doing and started over following a tutorial from YouTube while using my KiCAD disaster as a reference. I also switched from KiCAD to EasyEDA because KiCAD just didn't click with me (KiCAD is the LMMS of PCB design, and I'm more of an Audiotool guy). Then I realised the tutorial sucked so I switched to a better one. After that I designed the schematic & PCB in a way that'll probably work.

KiCAD abomination:

EasyEDA schematic (sorry abt the quality):

PCB design:

Planning/research for parts

Here's the stuff I think I'll need for the calculator:

• Mobile chipset: probably MediaTek MT6580, very slow phone processor but will be more than good enough for a calculator. Also, only 15 bucks. Image:
• Screen: a standard AliExpress 2.8in-3.5in display will work. Image:
• Battery: just going to salvage something from my phone collection
• Keyboard: I'll need to make a PCB for that
• Case & buttons: 3d printable
• Software: Android custom ROM I'll make!