You are trying to make as if Bannerlord has plenty of new and exciting features. It doesn't. Just two in your list, to be exact.
Content in parentheses is the comparison with Warband.
- Siege equipment like battering rams, catapults, arbalests, siege towers and two sets of three ladders, most of which can be destroyed (only one ladder or invincible siege tower)
- Combining parties into one giant party to form an army (you herd lords and have them run away at a seemingly bigger party)
- Perks that also give bonus to your party/army or governed settlement (only raw stat bonus from skills and proficiencies)
- Weight-based inventory that lets you carry more items (fixed amount of slot that can only be improved with Inventory skill)
- Sending companions and some troops to do quests for you (non-existent)
- Making and disbanding parties led by companions or family members (once you name a companion a noble, they're no longer yours)
- Making your own caravan parties that move on their own (non-existent)
- Proposing to change kingdom's policies without being the leader (non-existent)
- Ability to select prisoners to recruit (you click a menu and the prisoners that are willing to join are random)
- Free militias in settlements (only a village has it and they're only peasants)
- Various buildings with multiple levels for more benefits and the ability to speed them up via funding, and queueable (build one at a time and there are no levels)
- Multiple workshops in one settlement (only one per settlement)
- Guaranteed capture after defeating lords (capture is luck based)
- Executing lords for stealing your cows that one time (non-existent)
- Multiple notable NPCs in settlements, so more quests (one guild master/village chief only)
- Horse and saddle/armor are separate items (horse and their armor is one item, making it hard to get good horses)
- Loot from raiding comes while raiding, and can be cancelled and resumed (you're stuck while looting and doesn't get the loot until it's finished)