Looking for a DSP without breaking the bank

I and hesitant to remove my 430 HU for put in an Alpine restyle until because of theft. Especially with top down and or doors off around here.

So thinking a DSP might and should give me better sound from my 430 HU.

Using an Alpine amp with Kicker/Alpine speaker combo now.

Sound is good as it can be from a 430, especially when streaming of an iOS device. Yes, Sirius XM not the best and what I listen to the most. Hoping a DSP will give me better sound.