Hi BabaPerson. Two quick answers and then a brief essay:
1. No
2. Not recommended. Stopping fermentation in mid flight is a lot like trying to catch a bullet between your teeth. It can be done - but it's done more by illusionists than by naive wine makers.
I have never made a kit and I am unfamiliar with the ingredients provided in a kit but my guess would be that every kit is designed for the yeast to ferment the sugar completely. If that is the case , and if the kit makers provide you with all the fruit sugar that is to be fermented then the only problems you might find when substituting the strain of yeast from the one the manufacturer of the kit provides is a) the yeast you selected cannot (for whatever reason) thrive in the sugar concentration they are now being asked to go to work in; b) the character of the yeast is not compatible with the flavors and aromas the manufacturer has designed their kit to highlight; or c) the mouthfeel of the wine aimed for by the manufacturer of the kit is no longer possible. In short the maximum potential ABV of the kit wine is fixed and the only thing you could alter by changing the yeast is to leave more residual sugar unfermented than the kit maker planned. Your wine really cannot have more alcohol in it simply because you selected a different yeast. BUT if you fermented at a temperature dis-preferred by your yeast or if the yeast was stressed then you may have produced what are called congeners and congeners taste "hot". I have no idea what the maximum ABV of the wine you made is but CR51 , I think is spec'ed to ferment to about 13.5%. Personally, I would never ask a yeast to work close to its limits. Putting a high demand on a yeast can also stress the yeast...
All that said, I am certain that kit manufacturers design their kits so that there is an optimum balance between the ABV, the sweetness (and that might be brut dry) , the flavor and aroma, the mouthfeel, tannins and acidity. When you modify this balance you need to do so fully understanding what you are doing: how will reducing the ABV affect the perception of sweetness, the perception of acidity etc.. Of course, the real issue may be that the CR51 fermented your must bone dry and dry wine may not be something you enjoy especially when the wine is as green (young) as it must be if you are talking about adding K-sorbate and K-meta to halt the fermentation.