I know that bass well and I think a pickup change could help. For one thing the stock pickups seem a bit too mild for me. Also there's a lot of noise when the J bridge pickup is mixed in.
I'd put in Duncan Quarter Pounders for the P neck pickup myself and change the bridge pickup for a noise cancelling type. Probably something from Duncan too.
Otherwise that's a very good bass. Can't beat the quality for the price. Nice neck too. They're selling in Canada for a little over $500 currently. They beat most Fenders in my opinion.
I don't know. Don't really know anything about pick ups.
I'm at music school right now and am playing a lot of different stuff.
Just maybe trying to improve the over all sound.