I liked the Hawaii Years to, BUT I hated many things:
1. Only TTK:
a) this made him weak against Fire,Gas,Electricity...and worked only when he was conscious..it made him much weaker than Superman which I didnt like
b) TTK is boring: Its ok as Extra-Power, BUT!!! TTK was only there to replace Kryptonian Powers, it had NO!! other important or cool Effect (yes there were some extras, but NOTHING was really crucial or superior to Supermans Powers).
c) There was the mission with the wave where his TTK could have been crucial, BUT his TTK didnt work on water..
2. Attitude:
ok this came later, but I really HATED the stories where he was reduced to a clown like when he played Batman and had a paper over his head etc.
At this time he annoyed me and also in the Comics Batman lost the respect and told him to stay away from Batgirl etc.etc.
I didnt completely like his attitude in TT, BUT at least he earned the respect of the others and wasnt anymore this clown.
I dont say Johns Version is perfect, BUT I liked that he became more powerful, more mature and also climbed up the ladder by fighting against Brainiac,Doomsday Clone, Superboy Prime etc.
If we are talking only Power based than the Kessel Superboy would be my last Favorite Version of Conner.
I liked even the NEW52 Superboy more than the Kessel one (POWER BASED).
If NEW52 Superboy would have had Kryptonian Super-Strenght (based on his age) and Kryptonian Invulnerability, than he would have been almost perfect.
I mean his Telekinesis and Telepathy gave him some interesting possibilities.
I personally would like to see the TT Superboy with a mix of the Johns Superboy and Hawaiian Superboy attitude.
Johns Superboy was to timid,to silent,to slow for me while the Hawaiian was to immature for me.