I am sure that there are quite a number of divers over here that wonder about the (primarily) US fixation about AL tanks. The standard tanks that most people use over here (apart from stages/ponies) are steel and only a few AL tanks get soldMark...
As well as adding trim weight pockets...you may want to try ''shot packs'' as opposed to hard ballast...they're more friendly to your BC and will shape shift where hard weights will not...I swear by ''Sea Pearls'' shot packs...
Assuming you're diving with a 3AL 80...you may want to upgrade to HP 100 steel cylinders...check out DGX for prices...if you're going to wear ballast...it may as well be something you can breath from...
Hope this helps...
W.M...
For me, steel tanks have far better properties for divers. Aluminium tanks IMHO tend to be harder to trim and make weighting an issue due to their tendency to be positively buoyant at the end of a dive.