Why not just build it down the side of an A-road, then it will be well lit and safe from Nonces (well, except ones with vans) but now polluted, noisy and at constant risk of vehicles running off the road and into people, or young kids darting off into the road, and the kids won’t get to engage with nature either.
See, we can rapidly start getting silly when discussing risk, can’t we?
Electricity supply instillation can magnify costs exponentially. It might be relevant in an urban area, but to demand it on routes through agricultural fields is getting silly, and results in fewer safe routes getting built (and that’s before we even begin to think about issues like light pollution, impact of lighting on wildlife etc.)
a practical solution on some routes has been photo-luminescent road studs, eg Britannia greenway.
https://www.youtube.com/watch?v=4NMm5LZo0IE