you're right. I kinda answered myself. but my heart is still with my TM Glock 17. and in fact, some simple mods and I can shoot with it very well (PDI or NineBall tight bore, NINE BALL Air Seal Chamber Packing - purple one, Guarder enhanced loading nozzle, NineBall recoil spring guide - with buffer included, PDI or NineBall piston head). I already did the mod you mentioned: I wraped teflon tape around the plastic outer barrel and I sprayed silicon oil on it. another mod I would like to do is stippling my plastic frame or making a grip pad from skateboard tape. so, there will be one thing unchanged: the plastic slide. which can be a future project.
but then I ask myself a question: is it wort investing more money in my Glock or I should stop here and buy a hi-capa? that is the question I can't answer myself to. and that's why I need your opinions and advices because I'm sure they are not new to you.