Much of the main cast are teenagers, and as such seem mostly complacent to the severity of the situation their country is in until it really hits home. They're not terribly concerned with fighting for their country as much as simply defending the stadium they race at, but by doing so effectively enter into the war. The characters are more or less fleshed out well, giving you enough reason to care about them once things start to get really serious, and hoping they make it to the end.
The animation is nice and fluid, not having many still frames and providing plenty of movement. And the character and mechanical designs are solid, with all the characters having very specific looks that make them all very easy to differentiate despite their similar racing uniforms many of them wear, and the various vehicles being very unique. Particularly that of the mono bikes and police patrol cars. I've always thought those were pretty cool looking. The music by Joe Hisaishi is good also, and really compliments the film well, adding much to the atmosphere of the world in which the film exists.
While not necessarily nihilistic, having first seen this the day after seeing Project A-ko, the generally solemn nature of Venus Wars was a shock to the system. I clearly enjoy it now as an adult, but I'm always a bit surprised by how much I enjoyed it when I was 13. Venus Wars isn't a fun film per se, and can sometimes wax poetic about politics, but it's great art designs, animation, and engaging story make it well worth a view in my humble opinion.