From your settings described, it appears you're scooping out your mids, which is the last thing you should do if you want to cut thru. Not only are your settings on the tone controls scooped, but you are scooping further by maxing the contour knob. Make adjustments during practice and start flat adjusting from there by adding mids and ridding yourself of scooping.
I came here to say this also - why would you scoop your *mids*? If you're playing solo in your bedroom, this might sound good, or if you're actually playing a solo it might sound good, but this is where your bass sits in the mix, and you're cutting out all the good stuff. This alone will make a significant difference. Turn the contour all the way off, and maybe drop your highs and lows to like 10:00 - this is likely where "flat" is for these settings, flat for mid is often at noon or 1:00. Turn the tone knob on your bass down a little, also to about 8-9.
Use heavier gauge strings? I don't know what you have for strings, or if you're playing a five string and mostly hanging out on the B. If so, a compressor should help.
A second 410 will not only give you the extra wattage that comes with 4 Ohms, it will also give you significantly more air to push, and will be a lot louder.
However, as has been noted several times, practicing at loud volumes will ensure that you as a band suck - because you won't be able to listen to each other or yourselves, and get tight. My advice is spend 3/4 rehearsals at low volume, and maybe 1/4 rehearsals at loud volume just for fun and to blow off steam.