2012 Tundra Audio upgrades

So I was wondering what route I should take regarding audio in my truck. I’m currently running kicker 6x9s up front and kicker 6 1/2 in the back door. Tweeters are stock and head unit is a boss cheapie which is somehow better than the stock HU. My issue is that the speakers feel underpowered. I used to have a subwoofer with a built in amp and when it was in operation the music sounded amazing and much clearer. One day the sub quit on me and I did not want to go through the trouble of fixing it. My friend tells me to put in a pioneer and it’ll fix my problem but I don’t want to spend money and lots of time wiring to he just as dissatisfied. What are your thoughts? I’m a college student in an internship so I definitely don’t have anything crazy to blow but there is some room to improve audio. I’m happy with the speakers but the HU/missing amp feels like an issue. I do all-of this work myself but I find myself working full time while going to school full time which really doesn’t give me as much time to experiment with this type of stuff. Thank you for your advice guys - Chris