If Vekoma intends for the brake to be a selling point of the ride, then I don't think it's a problem. I think Intamin are putting a similar sort of element onto Parc Asterix's 2022 launch coaster, correct me if I'm wrong. Besides, you don't tend to go over tall top hats like that with a huge amount of speed anyway, and you should still get some great ejector over it in the back!
Also, it might be worth remembering that Vekoma will have engineered this coaster with the trim in mind; without it, the ride would likely be too intense and subject its riders to too much g-force.
With regard to the ride looking slower than Lech Coaster, that might not necessarily be a bad thing, as some people find Lech too intense. The ride might appeal to a wider demographic.
Having watched the POV, I think the ride looks fantastic! The launch looks nice and punchy, it looks very smooth and comfortable and it looks to have some really fun elements, with some nice hangtime in there!