You will typically not find good trance kicks in a general-purpose soundfont. If you want to be able to create good kicks from scratch, you could give the
Kick 2 plugin a try. If you prefer some free samples, you will often find demo versions of commercial drum packs which only contain a fraction of the sounds but many of them are very usable. I like the kicks in
this sample pack for example, and it's very cheap too.
Saying about putting reverbs on low frequency, I experienced sound saturation(clipping) when playing midi files including bass and sub-bass with soundfont. And now I know the reason why, thanks to you.
In general it's a bad idea to just put a global reverb on a song. I know people love to do this to MOD and MIDI files; I used to do something similar when I discovered the magic of VST plugins in MPT and as a result my tracks from that era sound terribly muddy (compared to terribly dry tracks from the time before that). Reverb should be applied in a nuanced way, only to the instruments that really need it, and different reverb settings (length / density / etc.) should be used depending on how much reverb each instrument (or instrument group) needs. Just applying the same big reverb to the whole song will make it sound like's played in a cave.