Stereo upgrade upgrade?

I seem to have fallen off the wagon with my addiction to buying things I don't need with money I don't really have. I'm trying to convince myself that I don't need an additional cheap amp and a pair of tactile transducers aka bass shakers aka butt kickers. Other brands are available. Thing is I already have a 4x100 watts head unit running a quartet of 4 inch Pyle blue labels coupled with a pioneer compact under seat sub. And it's ok. I mean it sounds loud but it's not a 90s magazine install. Yes it is compact and then some which is useful in a load carrying Jimny but it barely raises an eyebrow at car meetings or more importantly with the scantily clad ravers in town on a weekend. The proposed update wouldn't be hard to hide as the drivers would secure below the rear speakers without cutting the plastic trim as they are essentially just voice coils without cones and the lanzar could go in the jack cavity or under the passenger seat. 

The thing is though I said I wanted mud tyres and this will be at least 2 of the cheap ones leaving a funding deficit for a set of 4. I know I said no more racecar parts but this is a boyracer thing not racecar. 

Arghhhh. 

I used to be indecisive but now I'm not sure.

ake bass is good for my tinnitus ,,,