This may seem off topic a lil bit but i would rather say it here than start a new topic about it. I don't like the fact that the hack box can be removed so easily by an engineer. But, when your on shipyard (i think lol) when the engineers have to repair the crane, if they get it to like 60%, there is no way of making that go down like you can make a hack box percentage go down and even remove it all together.
I don't think one objective is easier than the other. They are just different. Its the teams that make an objective hard or easy.
HE Charge: Average plant time, with an average countdown. Quick or quicker defuse time. No commutative planting (only one bomb), not sure about commutative defusing.
Hacking: Quick plant time. Can hack from a distance. Variable progress (distance and los) and defuse time (progress made). Commutative hacking.
Repairing: Long progress meter. Permanent progression. Fixed to objective when repairing. Commutative repairing.
Honestly, I think repairing carries the highest risk as I'm right out in the open hoping for adequate cover from the teammates. I also use the sense of perspective, which helps, but my reaction time is still slower than when I'm hacking.
When hacking, I can hide while making progress and quickly pull out the gun when needed.
HE charges are just easy (well usually).
As to the spawn nodes...
I think when you complete objectives (as offense), generally your next objective will be a bit further away from the spawn zone. I'm not certain on that, it does seem like it though.