it will sound 10x worse with the equipment you buy.
The only way it'll sound better if you use your whole budget for a proper head unit. Your stock speakers will become a completely different animal with a proper head unit in.
DO NOT swap the stock speakers. Not unless you are fully comitted into making acoustical door treatments turning your vehicle door into a speaker enclosure. Along with recreating the factory seal and a proper baffle to redirect the sound into the cabin rather than the sound waves getting stuck in the door cavity and fighting eachother.
If you do not do this step along with amping the speakers, The setup will sound like sh*t if you swap speakers.
A proper head unit will make music sound amazing right out the box however it'll have tuning options to make speakers sound amazing. Basically your stock speakers will sound like you just spent 200 dollars on new speakers if you tune it right with a new head unit.
TLDR get a good head unit, do a proper tune and you'll have 100x more results than swapping out for junk low end speakers yes those particular kicker and pioneer speakers are low end junk. That kenwood x301 is a good choice Head unit upgrade first before doing ANYTHING. dont look at junk head units either there's a reason why we recommend particular head unit models.
stock stereos are beyond garbage. You only get 3-5 watts of power per speaker with a stock stereo. Also has ZERO tuning options. What makes or breaks your system is the EQ, time alignment and power. Something stock stereos can never achieve.