Siege research is really bad, it feels bad putting points into most upgrades. I don't think there is a reason to make the upgrades this useless.
Level 7 20/20 - 20% production time, 20% atk/hp on terrain or 30% atk/hp loan Rakan
-Production time is really horrible upgrade, there is actually noting worse that you can get. Why is this even a thing. This could have easily been hp+.
Level 3/11 - Siege Plating 10%/20% range damage reduction. Why not at least make this all damage reduction, why just ranged, and does this include magic? This is far too weak of a bonus considering the level 11 takes 1000 hours and 4.8 million resources to finish.
Level 12 - Honor Bombardment 30% more honor for attacking walls. This is really really bad, again a huge investment and you get nothing in the end. If you want to keep honor at least make it 300% or something that would give incentive for people to research siege. Make siege have 2 per pack, make them get injured or get 60% resources back on death, or give them 150% more damage to normal, 100% to large, and 50% to massive units. 30% honor is far too little and irrelevant to invest so much into.