Hi guys, atm im just wandering is it worth buying/replacing these things: (atm im not looking for major upgrades/changes...just very minor ones as i want to keep my car near stock as possible with a limited budget...the only thing i've done is an injen intake)

1. Dc5r stock head unit?? it looks so plain n low on features (e.g. Ipod dock, eq,etc) replacing it with alpine/pioneer Head Unit only would improve the sound or anything at all? Even if its still with the standard speakers/tweeters?
2. Muffler?? since im a cheapo, cant afford/dont want to buy the whole exhaust system (as mentioned i want minor ug @ limited budget), i only want the muffler for better wow factor/sound/rice...is it worth it??
3. HID?? 6000K..I dunno why but it just looks better with hids...is it worth??

Thanks in advance and please tolerate my noob ness.
Cheers

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