I feel like the directional shield blocking could be somewhat appropriate for cavalry, but not infantry.
I hate having to point the camera at an archer with the shield up, and then having to adjust the shield's direction. You'll often get shot before it's redirected, and it feels ridiculous. But with cavalry it makes a lot more sense to hold the shield at your sides to block arrows or enemy cavalry attacks while looking slightly forward. (Shield mechanics on cavalry were always a problem in Warband, I think just because of the limited animation not showing how far they could cover themselves against melee attacks.) If Bannerlord's shield mechanics are cumbersome, then maybe cavalry deserve to have it (not infantry) as a tradeoff for their other abilities. Although, again, it could actually be a useful feature for them specifically. It's a strange situation where I want cavalry to have more tradeoffs/downsides to make the superior class infantry be less frustrated and hard done by, but whenever I do play as cavalry I feel thankful for how much you can get away with.
For infantry, in Warband, the normal shield mechanic was very quick, intuitive and satisfying, and I would much prefer it. Pointing quickly with the shield at different oppenents' incoming attacks is a lot better. Bannerlord's directional shield blocking for infantry is cumbersome and pointless. I was hoping they'd improve upon shields for infantry by removing the ridiculous features of footshots and shooting through shields, but it looks like it's become worse. So, in summary, I'd just remove the directional shield blocking for infantry.