OK, good. Then let's just see how growth goes for you w/ your current set up for a while. I found it real tough to get good growth out of vals/other background plants myself, as the side of the Eclipse filter blocked my middle area lights from hitting the back of the tank. If you find you're still needing more light later, or would like more even lighting front and back, your next option would be cutting out the old filter space. If you do go that route, it should be relatively easy to rig up another couple ODNO T8s in that space relatively cheaply. T8 bulbs and bulb holders are cheap and easy enough to find.
Btw, some here would disagree, but I never worry about using a glass top myself. The lights in my hood are left unprotected. Though I'm careful about splashing while doing maintenance of course, I've had no busted lamps or other problems.