Your suggestions sound very interesting, but I'm still not sure how I can include some of the features such as different ball types. The velocity attack is easy because all I have to do is just adding one menu option and having the game record speeds of the ball every frame. If I were to make different balls, some things would happen; one for sure is that 10 stages are not enough. It would be great if I could make some stages and levels like BK3, but it wouldn't be an easy work because the most important job for me is currently BK3 translation.

You can get the ball to be stuck not only below the paddle, but also to its side. The ball is probably bouncing off the paddle, then hitting one of the side walls, then bouncing back to the paddle and so on.

As for powerups, I would love to see them in the arcade mode. Most mainstream breakout games give you powerups inside blocks that appear randomly on the board on occasion, so all you have to do is break a powerup block with the ball to get it. Things you can usually get range from extra balls, different kinds (like the fireballs someone mentioned earlier), larger paddles and so on. Most of these powerups are timed. Another one I can think of that would be good for this game is a low gravity powerup, or one that would give you a second ball that would remain in play either for time limit or until it stops moving.
On iOS, blindfold breakout uses a shop system, where you can use your points to buy yourself different kinds of balls, but I'm not sure how well such a system would work in marina break because you're not really supposed to lose your ball. It might still have a use for possibly getting one-time use special paddle swings that could for example hit the ball with twice as much force as a normal swing would.

Nods, the power-ups  would probably have to be on a completely different mode, so that the score attack scoreboard would still be an accurate metric for skill.

I guess both could have their own scoreboard, I think velocity attack would be nice to have a scoreboard as well if it gets implemented. Not sure how easy it is to create more boards but it would definitely be fun. But I do agree that we need to keep a score attack without powerups too.

Unfortunately, it isn't supported. I'm separating each source code, so anyone who try translating the game will need to read the whole source and change any required strings written in it.

The new game modes are lots of fun. I somehow got a velocity peak of 150. I guess that's what repeatedly hitting bonus items can achieve, but its very random if you can manage it or not.
I'm not sure how doable this is, but could we have the different block sounds also in the attack modes? I'm guessing they sound different depending on the width and such, but I really like the wooden block sounds for example and it's a shame they can only be heard in the tutorial and the missions. Although admittedly playing level 10 and trying to get the best time possible is fun too, I think my best time is just under 4 minutes.
Hmm, I was going to suggest some other small thing, but I forgot. Perhaps I will remember some other time.

Arjan, will you record yourself playing this? I can't seem to get scores above 1334, and my highest velocity on velocity attack was 22. I just am curious to see your strategy, kind of how you guys do it. I'm not asking for a narrated walkthrough or let's play, just a quick recording of a game would be fine.

A lot of the reason for success in this game is experience. You just have to play it a lot so you can figure out the movement patterns of the ball, and what keys to use.

The practice mode is a good way to know when the game will let you hit the paddle for instance. Maybe some people are a bit off.

Another problem I have is the one mentioned earlier, --I've looked back on it again and discovered that it is in fact, not the ball getting stuck between the wall and pattle. Instead, the ball could be right over me, I slap the x key, and it gets stuck on something and then loses a lot of energy. Then I realize, I'm not really near a wall. I usually am doing quite well until this happens...

Version 1.04 is out.
2016/02/06 Version 1.04
Added : You can now toggle powerups in velocity attack. Note : In order not to screw up the ranking, results of velocity attack posted by the older versions are blocked by the score server.
Added : Pressing the S key while playing velocity or time attack speaks your current score.
Fixed : The game no longer counts false scores when the time is up while the bonus blocks are being generated.

does it need updating? It seems everything is already there to me.