im also a big lover of car audio, so much so that i opened a shop to share my love with customers lol
my car previous car had similar goals but i held sound quality and price over weight
Alpine CDA9887 head unit, 16wrms x4, active crossovers and time alignment.
Tang band W4-1320SJF wide band 4" in fibreglass dash pods. (would have used the neo versions if weight was a priority over price)
Peerless HDS 8" mid/sub bass in MDF floor pods. (again would have used neo woofers and fiberglass pods if weight was a priority over price)
the 4"s were high passed at 300hz 12db/oct and the 8"s low passed at 300hz again at 12db/oct.
played within 3db down to 30hz and over 110 db at full noise.
the floor pods were built as putting the 8"s or dual 6.5" in the doors would have weighed more and cost more to get the same low end extension due to the cost and weight of deadening products.
a couple of pics: