Bear in mind here the original post and the entire thread is gen 3-6 so unless it's posted in the wrong thread all the info is not really useful. I notice that the OP has a gen7 2013 so the above does apply.
A good exhaust will give decent results and get the heat out of the engine better. If we are talking gen7 then an ECU retune combined with a good exhaust makes a really big difference! Well worth the $1500-2000 to get great increase in power/torque. Start with the exhaust and you may be happy, add the tune and you'll really smile!
Fuel economy is also a bonus if you drive it carefully. I get 7.3lts per 100km and 13 towing 2.5tonne.
My 2013 auto D4D DC SR5, prefilter, 3" exhaust and Chip with egt probe, stock SR5 rims with Toyo Open Country AT2 265/65R/17's