That's what we are doing over our 30" gas range.
In fact that is the recommended safe & efficient way to capture smoke - when your hood size is overlapping the edges of your cooking surface.

So you have the expanding smoke width covered, how about your depth?
Most cooking surface is 24" deep & you should try to capture the rising smoke that expands 360 sideways & backwards & forwards.

Most mass produced hoods we found fall short of this 24" depth requirement. So the conversation may fall into the custom hood arena.

So look carefully into the specs.

Luckily, we found a hood from Broan that matched our WxD and CFM requirements.

Good luck to you!

It is not only a "good idea," it is the best way to do it.

Do a search on range hoods here and you will see that there is a general rule of thumb to have a hood that is the next size wider than the width of the stove. This collects more steam and etc. from the stove. When the hood is the same width as the stove, and not confined by cabinets, some of the vapor will curl out beyond the hood. A wider hood diminishes that. So, 36" hood for a 30" range is recommended. (As you have a 42-inch space, you could go that wide, if you wanted. A more powerful hood can generally run at lower speeds and thus be more quiet. OTOH, a 42" hood is going to be a lot more expensive.)

There have been a lot of postings on this subject. Do a search and you will find numbers of redcent in-depth discussions One of the most helpful and knowledgeable GWers on this subject is Kaseki.

Something to bear in mind, though, is the CFM rating. Some cities and towns have adopted codes that require make-up air (MUA) for hoods that pull over a certain amount of CFM. Codes vary. Some posters report that 400 CFM is the point where MUA is required, others have 600 CFM.

MUA can be a good idea idea even apart from code requirements because it prevents CO backdrafting from elsewhere in a tightly sealed house (say, from a gas water heater or a furnace). Search on MUA here to get more information.