Most "mods" are just for appearance and making more noise.
You can spend >$1000 easily on a full exhaust and ECU manager on a 300 and maybe see one HP. Tires and pads make real differences.
Kevin Cameron has one piece of advice in his book , "Sportbike Performance Handbook", up front, in that there is a myth that adding parts to a bike will make it a better bike, but he suggests making a list of all the planned mods and take that money and buy a better bike. There's always a guy in his parent's garage who thinks he knows better than a team of PhD engineers in Japan.
For God's sake, keep away from eBay LED flushmounts.
Also keep in mind that modding a bike does nothing to add value, and will likely hurt the resale value. If you insist on doing this, make sure you keep the stock parts and can revert the bike back.
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