I have no comment on your modification other than if it works for you, great. As far as simply mulching the leaves in, I'd say if you do not have a premium stand of whatever grass they use up there, you may as well do it. My 'yard' is probably like yours. I've basically given up on it because of moles, voles and deer. The trick to mulching-in leaves is to stay at it and catch it before they cover the grass. During heavy leaf drop you'll have to run the mulcher every day sometimes.
There is also an alternate method - mulch first then go back over it with the bag on. Volume of leaf material bagged is probably about 1/10 of bagging without mulching first. Not only do the chopped-up leaves take up much less space, about half of it is dust that stays on the ground. This way you have much less material to dispose of and the lawn looks cleaner and more 'manicured'. Plus, you can take the bag and deposit the leaf material around trees, shrubs and in flower beds. The stuff decomposes into dirt ten times faster than just piling up leaves.
Finally, research has shown that generally mulched leaf material and mulched grass is good for lawns and builds topsoil depth and quality.

I've been mulching leaves in Michigan for about 7 or 8 years with no harm to my yard. Best to mulch when dry and it can take a few passes. I use gator blades on a Snapper 21 with mulch plate and have used a LB 21 inch with gator blades. We moved to a house with much more yard and more trees a few years ago. I had a mulch plate made for an old Wheel Horse rider deck, purchased gator blades for that deck and it works great for mulching leaves. I sharpen the gator blades at the beginning of each season. As long as the leaves are mulched fine enough to leave grass blades showing it seems to work great. Dry leaves also clean the deck out. I also blow the leaves from the landscaping to the yard to be mulched. Haven't raked, bagged, or burned leaves in years.