Is this a good list of upgrades?

So I was thinking of upgrading a CYMA M14 with the following list. Do you guys think this is a good list and what changes would you recommend to the list? Also is the CYMA M14 a good base gun or should I go for something a little more expensive, and if so which gun would that be? It would have to fit in the budget, so with the gun someone might recommend is a better option to the CYMA M14 could you tell me which upgrades to keep and which to not buy to fit my budget? But I did a poll on Airsoft society and everyone was going with the CYMA M14 as a base gun.

PDI 190%-$19
Modify Tempered stainless 8mm bushings
Either Firefly bucking-$20.75, or Systema bucking hop packing for airsoft aeg-$6.75
regular old nub,(I hear there are different versions)-$2 or so
Prometheus Aero cylinder head for ver 6-$12
Deep fire Aluminum air nozzel-$10.10
Systema area 1000 cylinder type O-$12
Either system super core-$50, or SHS piston ver. 2/or 3-$15
Systema Energy piston head w/ball bearings- $25
Extra O rings(not sure which type)- think they are like $6 for 6
Prometheus version 2&8 spring guide w/ball bearings- $24

Not sure which high torque gear set to get so I got the ones saying they were compatible with M14,
prometheus Normal type torque gear est for ver.7 (TM M14)-$100
Prometheus high speed gear set for ver 7 (TM M14)-$100
prometheus EG double torque gear set for ver.7 (TM M14)-$100
Gate GDS-4004-AB Mosfet with active braking- $50
SHS high torque Motor(short)-$39
Modify Torus Ver.2 reinforced 8mm Gearbox w/tappet plate-$73
Element reinforced hop up seal chamber for marui type M14 series Airsoft AEG-$19
Madbull airsoft 6.01 ultimate tightbore barrel-$40

This comes out in tottal to be 466 dollars, but I need to drop a 100 dollars or so of stuff to pay for the CYMA M14. What would you say to swap out? I'm going to follow the mods on the holy grail thread to make it shoot better so I don't just do a lego build here.