Only you are able to determine the value of the "view". We have done GV and LV in concierge (Hawaii) and LV in the now Tahiti building. Our kids were younger when we opted for these pricier views. I suppose it was worth it when we were back in our rooms by 8:30 to 9:00 p.m. because the kids were ready for bed. It gave my husband and I a space for alone time in very close proximity to sleeping kids.
Now that they are older, I can't justify the additional, what I consider significant, per day charge for the view. We are rarely in our room when everyone isn't sleeping. Further, we prefer to view the fireworks from the beach in order to have the music as well as the lights. If we want to be indoors--there's always the lounge (at least while Hawaii remains open). So, for us, no--LV concierge isn't worth the additional $50-75 per night difference. I'd much rather add another pricey meal or buy a more expensive souvenir.
Tikiman's website has great information about room locations for LV--the most desirable, etc. As long as you are aware that 3rd floor is smoking optional, and you're okay with that, then you should be very happy with that floor. Don't forget, first floor has patios if the smoking issue is a problem for you. We prefer a location midway down the hall to the end opposite the lounge. You don't get the running kids in the hall as often and very few people utilize the east end stairway since it's an outside entrance. That said, we've also had first floor in close proximity to the check-in desks--maybe 4 doors down--and it was fine with us too. We've never had an "obstructed view" in any location. We did have a partial obstruction in LV, first floor, last room at the east end. Lots of foliage on the right side of the patio. . .
As I said, head to Tikiman's site and you'll be able to see just which rooms are the "best" in his experience. Have a great trip--we're headed down in June!