Emulating Percussive Sounds?

[MasterProX]

Arranging this piece as part of a medley for my school's string orchestra... and I can't seem to replicate that rhythmic drive you get from the drums, on strings — I was planning on having the basses pluck some of the rhythms, but it sounds rather... too fast, at times. Should I just bite the bullet and include drums in the instrumentation (and possibly expand it just a tiny bit outside of only strings), or does anyone have a better idea?

[Tobbeh99]

I would not do them pizzicato, but arco with staccato. And ignore the snare drum, and make the basses play mostly quarter notes but with some grace notes, like what the bass drum plays.