I would just like to suggest the Ancient Warfare mod, not for warfare reasons, but for castle gates in the Structure chunk of the mod. The mod author did it well so that the mod is split up into chunks so that you don't need to get the other unnecessary parts and could just get the structures, so I thought this would just be a nice thing to add in if it doesn't really break anything.
Also Decocraft is a really cool mod that has a ton of aesthetic items and useful ones like wood/rope bridges. It is very detailed and can be used to make really cool builds.
They both allow use in modpacks (Decocraft needs to be credited, Ancient Warfare can be used freely) and are 1.7.10 compatible.