You want range - TM Recoil
You want smooth running - TM Recoil
You want higher ROF reliably - TM Recoil + BTC/Titan + gearset + EagleM90 + 9.9V
Get a new if your budget allows or used Recoil, + those 4 mods will achieve more than youve probably ever expierenced and last a very very long time.
Get a solid base gun and get the internals done then leave it alone inside;
I know this looks quite different, but better to start with something like this https://airsoft-forums.uk/classifieds/item/10003-tokyo-marui-m4-cqbr-recoil/ and change the externals as you please over time.
Best
Dave
EDIT: Wanted to say - spend once wisely, get the base gun and save for upgrade later if needed. The stock TM is simply amazing anyway.