front firing vs side firing woofers

It's the speaker and room acustics. Side fireing given the same woofer and quality tend to feel a bit slower and sharp than front fireing but if you are loosing sound in a frequency range it probably has more to do with position and the room. If your speaker has a crossover try adjusting that.

Placement, Placement, biggest real way to gain or lose low freq. Try them 3 ft out from the backwall and then 1 ft, etc... and everything inbetween will be more bass punch but more smooth soundstage etc... So go as far into the room as possible and increment back toward the wall in small movement until it snaps in where you like it, but this may also need to move in and out from the side walls as well to re-focus soundstage.. Also, Try the side fireing in toward each other and fireing out toward the walls, I would guess they are a mirror pair. Welcome to the tedious and rewarding world of speaker placement, its tuff and I have been thru weeks without settling on new speaker placement but it will find a spot at some point.
A lot of the time I would listen to something not bass driven and thought it is great but then put in something I know needs more and they gotta be moved back an inch or so to gain bass from the backwall, find the best medium.

In my opinion, the type of bass to strive for will have the feel of a hammer (perhaps a rubber mallet) knocking you right in the sternum. As apposed to say a 500 lbs. bowl of jell-o knocking you in the sternum.

Not every recording has this type of bass, but many more than you may think do.

To achieve this level of punch and definition proper speaker cables and interconnects, and proper amplification are required to provide this type of deep, absolutely controlling, well-defined bass. Especially the amp.

That's assuming of course the speakers are up to the task.

To be safe, I would certainly prefer forward facing woofers as I think (contrary to what many say) the sound of lower frequencies (30Hz - 80Hz) can be quite directional. But again, this depends on many factors.

-IMO

That three dimensional bass wave that you can almost see rolling towards you across the floor can be musically distracting. My front firing floorstanding KEF's had it and they went way loud without distorting. Tight well shaped bass waves do have heaps of geewhiz factor but because they draw so much physical attention to themselves coming at you, they're ultimately annoying. Overall, I'd say hearing good bass is preferable to being forced into watching it. You're better off than you realize.

If you want slam (this is counterintuitive, but bear with me)... you need to get rid of resonances--by their nature, resonant frequencies take "some time" to resonate and also to decay.

Thus the koan: to get more bass, you need less bass.