No. If Bb-D is a 10th interval and it ends on a 5th interval, which is implied here, the bass is ascending from Bb to Ab (a 7th - check OP´s fifth post), while D is ascending a half step up to Eb. If bass goes down, you are right, but then we are not dealing with a fifth as ending interval, but an octave + a fifth. Alternatively Bb-D could be a major third by which Bb would be descending to Ab, while D goes up, and you would have the legal contrary motion.
As an extra note, in classical counterpoint Fux style, no leap greater than a fifth is recommended for choir voices to be singable (tho no leap in tritonus would be allowed), except for an octave or minor sixth in upward direction only. So you´d had to reach the 7th above Bb by oblique motion in this example to make it 100% Fux style. It is another deal with instruments of course.
As to personal preferences, they are irrelevant when you train strict counterpoint. Some CFs allow for one solution only, and if you do not follow the rules to an exam, you either won’t pass or will get a lower grade.
(and neither to use percussion). 2) It has choir voices, which quite deliberately move in the forbidden parallel fifths and generally make use of open intervals. This to get a pre-Fux taste too and to leave room for the harmonized melodies. Palestrina would be more into open intervals but hardly as bold as I use them here. Everything is counterpointed to the harp by default. Thus it is some genre mix but draws on a few classical sources. I do not think I would be able to do it without training. Natural talents may, but I am no such. Got to get it in with years of practise. 
