correct. it has huge room for optimization. I've even seen people use the dot display as RAM, I could have utilized that because the RAM chip is the main component that heavily affects performance. but I was aiming mostly for a conceptual and intuitive design rather than an optimized one
XD I understood You , now I almost done ALU in mos6502 but I use only NAND some times looks like a pasta , BUT WORK as well XP
About RAM Use RGB 8pin for address and 2x4 bit for data (more data in one place ) and if you use only data without address You will got a register ( Load pin conect to save refresh and clock , Read use 2 4to1 bit and use 8 3state buffer)