The trouble there is, it's not going to be as simple as turning the controls on and off. The game from this point onwards is going to be designed and balanced around the assumption that you can aim in any direction that you want with ease. So enemies could be positioned and attack in ways that require aiming abilities that the old system likely would have extreme difficulty targeting.
So you're basically saying that it'll has extra difficult, well I'm in...
Think about some features such as "auto-dash at jump peak/always jump at max height" and think what makes more sense...
I feel more comfortible on playing with keyboard only, but if it goes with mouse/keyboard then I'll not be able to play anytime soon and many other can endup dropping it entirely so...
As a developer myself (not a game developer) I think the dev should do what it wants and the costumers should deal with it, but it is wise to take others opnion in account while still in development stage... =)
Finally I'd say that the feature "toogle blaster" would feel better if it was like mega man x's "auto fire". The way it is now you press the button then Alicia turn on non-stopping fire and you has to press again to turn it off, it feels like mobile games that does basic actions fully automatic and amost plays the game for you, it would feel better if it was fired while the button is pressed and stopped as it is released...
Again I'm not asking the dev to take out mouse feature, I'm asking him to make the controls enjoyble to me too the way it was before and if he isn't willing to do then its fine too. It's not a complain just a opnion based on my current setup...
Regards...