1. Most favorite: I love the premise of creating a goofy experience with the archers as little minions that stand in contrast to the invincible Wallther. I think the synergy of the two will create many unique, surprising and fun moments that players will enjoy. 
2. Least favorite: I don't like that you can't see the enemies because I think the scenery can get dull over time and there's also no way to anticipate where the wall will be attacked.
3. Improvement: Foreshadow which parts of the wall will be attacked next. I'm thinking of indicators at certain points or siege towers the enemies build at a specific location. Perhaps there is also a way to indicate whether the wooden or stone parts will break.

(1) I really like the idea of your little guys representing the health bar. I think that's a very innovative way of handling the player's health.
(2) I could imagine that your game, having no clear goal/gets more difficult over time until the wall falls (setting the player up to fail), can become a bit frustrating for the player, especially when they play your games multiple times.
(3) Maybe you can add some kind of achievement system or personal high score, so very good runs aren't completely lost when the player loses the game.

1. Most favorite: I like the idea of doing without the UI as much as possible and displaying all the necessary information via visual in-game elements. This can make the chaos even cooler and more natural.
2. Least favorite: It would be cool if the main character could do more. e.g., throw down the guys who are climbing the wall, or if they are already on the wall that you can throw them back again.
3. Improvement: It could be cool if the camera moves slightly or vibrates when a part of the wall is destroyed. 

1. I really like the setting and the idea of your game and I believe the artstyle you have chosen can make for a cool experience.  Having an "infinite" game makes for some great opportunities to challenge the player on decision making and time pressure. The contrast between Wallther and the puny crossbowmen definetly adds to the comedic aspect of the game.

2. Having this infinite game is fun but I can imagine that your game can get rather repetitive if you only have this one level as after playing the game once you rely solely on the players desire to beat their high score.

Also, you will have to think about the layout of your level, especially with the catapult. In your presentation it did seem like a central aspect of the game, however, it is located "far" away from the action. Especially in later stages of the game when it gets more hectic this might pose a sort of bottleneck for the player. 

3. It might be interesting to introduce multiple levels with different wall layouts  or have variing difficulties. You mentioned in your presentation that you wanted to make something infinite like "Temple Run". In this game the scenery and the level-layout changes while you are running.

It might be interesting for you to add some sort of change that can occur over time. You could change the level layout after a set amount of days or add events that force the player to adapt.

- I believe that the fast paced, arcade style gameplay of Wall-ther would definitely create a fun experience for the player. I really like the fun and goofy atmosphere of the game and the chaotic nature of the gameplay,

- As others mentioned no clear end goal might feel uninteresting or repetitive after few levels. Some kind of a leaderboard system where players can compare themselves with others or maybe even a basic local multiplayer where players try to survive longer than others might improve the game even more.

- Different levels with different layouts and themes and few added challenges or obstacles could be fun. 

1. I like the setting of the character. The idea of this really buffed guy only caring about repairing the wall and ignoring everything else seems very unique and funny to me. Combining this with the whole ancestor story is a nice touch as well

2. As much as i like the setting of the character, it also limits you in the options that can improve the gameplay over time. As you have mentioned, wallther being this invincible guy really limits the kind of improvements he can receive.
Furthermore, only seeing the wall from within might be weird as you don't really know what is happening from the outside 

3. As others have written, different layouts are a nice idea to mix up the gameplay a bit. Maybe even have levels where there are multiple walls that have to be protected

1) I like the setting and the idea itself. It’s nice to have more casual and arcade setting, also character is easy to remember and associate with the game, so it is a good decision to put his name in the title

2) A game can become repetitive, since there is no clear goal and story.

3) I think you can make it more interesting by adding bit more of a story and lore  (like some info about why somebody wants to attack the wall at all), maybe some types of attacks that can buff and debuff Wallther (like frozing him, slowing him down), that will appear one by one, so the player has enough time to learn them. 

(And sorry for a late feedback, I completely forgot about it)