If you'd rather live with that mentality, by all means do so. Techer isn't weak and it's very underestimated. Te/hu doesn't shine when it comes to explosions but rather the smack itself, since the explosions scale off t-atk. Out of the all the techers, namely (Te/hu, Te/ph, Te/et, Te/fi, Te/br), Te/hu in global will be a thing that provides everything you want (Damage, survivability) until te/ph is out. I don't know if NA also has the sword "Dragonslayer" and it's weaponoid potential, but if you are so hellbent in wanting to go like that, you can go look up if the dragonslayer can be potential unlocked to have the 80% something stupid more damage on each of its normal attacks and use that instead. If you think your class is gimped, you should just stop looking at techer itself and look at the game itself and see what you can use as a techer to improve it. Live with the mentality people put on you and you get no progress. Keep experimenting. It also depends on what weapons techer currently has available in NA, which I don't really know much about, starting with Lavis Cannon, Wand Clover S ability or whatever it is on Atra weapon. There's even an R ring that you can use to stack up even more damage on smack (doesn't add up on explosions though). Too bad you'd rather be forever grumpy about it. You can say as much as you want about techer being gimped, you can be selfish as a techer and do what you want too, but at the end of the day, as much bullshit you speak of techer being weak, a well placed zanverse where everyone in an mpa makes use of it, can cut time of an UQ from mere 20 minutes down to 10minutes, sometimes even 5 minutes, as many JP veterans have observed in a Luther EQ @ UH, where it doesn't even last 5 minutes because of all the zanverse damage, since it adds up damage to everyone. It also can make fighters go from 75% critical rate to 100% as well granting them damage reduction to survive under limit break.
Most of your argument about other classes mobbing better than techer currently is due to the fact that, global is being bombarded with content and equipments or buffs that when said quests were made, they didn't exist or/and balance wasn't like that back then. Global pretty much nitpicked a lot of balances from the current EP6 from JP. Global is pretty much living EP4 with balances or adjustments made for EP6.
Similiarly, it also depends on your gear, in which you said it's all MEL. How's your weapon looking like though? What weapon is it? What is the potential of it? How much % is it? (%Dmg is better than flat stats). How many S abilities does it have? There's alot of open options to you if you still want to go dps route rather than support, like for example, TeFi with chaser skills @ skill tree, since they can change elements with a ring, although it requires you to cast x element technique to change it, don't know if the ring exists in Global. Te/hu with a sword, using Sonic arrow to charge gear and rising edge/twister drop for damage. However, one way or another it's still gonna be a support, having damage or not, it's still an important class regardless of what you say, since a techer is able to inflict status far easier than most classes, since they can use a specific weapon series as gunblade, cast techniques and those techniques will have 150% more chance to inflict status, contrary to other classes that need to have status as an affix. If people call "Techer" useless for anything else other than just buffs and zanverse, they are gravely mistaken. There is a reason why when people were doing endless for 4man titles, meta back then was Hero, Gunner, Techer +1 ( don't remember which ). Good luck, though.