Very Few bit's from TM are worth it anymore considering the price of other cheaper Clone's that do just as well Eg M14-Cyma, AK-Cyma, JG-Scorpion & Well's MP7 AEP. Their Pistol's barely Rate anymore IMHO unless it's a Custom or Rare Pistol-KWA Their Old M3 Shotguns are seemingly over priced because of DE, So the Long and short of it is VSR's or Recoil Shock's
-The TM M14 is still holding well for it's age. External quality is great and still performs excellently.
-The AK47 is bombproof and last forever. I agree that is has fallen behind though. LCT,VFC and CYMA are the go to brands for AK. It can be purchased pretty cheap.
-Well scorpion and Mp7 are not great,but the JG skorpion is quite good.
The TM Mp7 AEP and Skorpion AEP are overpriced as hell though,even in Japan.
-Tri shots badly need an update,they are very good but they have no support for spare parts. You can get an M3 for about 150$ is Japan though,so they still justify their price,just barely.
-Pistols are still good,but only say,post 2006/2007 ones. KWA is very good,barring their not so great 1911s. TMs are expensive outside of japan,but justify their price.
But otherwise your right,VSRs,Recoil shocks and the high cycle range is their main focus.
Old TM prolines do not justify their price,barring a few models(P90,ak47,type 89,AUG)
TL;DR: Buying a TM? Recoil shock,high cycle,VSR,pistol or GTFO. Oh, and buy from Japan or you will have to stop eating.