The Midtown Tour will almost certainly require 2+ days to navigate through all the landmarks & destinations & could be included on all tours to break it up as a starting or finishing point to take in events or restaurants in the area.
If Times Square is your central point be prepared to be squashed walking through among all the tourists in peak times or weekends! Best time to just see the square is probably before 8:30am or after 9:30am once people have gone to work, avoid 5-6:30pm at all costs after people have finished work & just want out of TS, New Yorkers despise TS & try to avoid it! A night time stroll is worth seeing everything lit up but again its busy. Dining is not really the best option even if you see the big lights of Red Lobster, Bubba Gump, Hard Rock, TGI Friday, Applebees etc. they are all over priced, if you’re desperate, Olive Garden (express lunch time only) or McDonalds is your answer. Even $1 pizza isn’t a $1 in TS!! I do recommend the Brooklyn Diner though on W43rd for a 15-bite Brooklyn Diner All-Beef Frankfurter!
Depending on which direction you leave TS, Bryant Park is worth walking through to remind you what grass looks like, where you can rest (find a chair first!) & take in life at NY’s pace. The NY Public Library is adjoining Bryant Park & could be a bit of respite from the heat or cold too.
If you continue east along 42nd St Grand Central Station is a short walk from Bryant Park or another central point whether you’re passing through on the Subway or heading out of NYC. Walk through the main terminal & get some photos on the East & West staircases. Fact, only the West staircase is original, the East was added in the 90’s.
Head out the north end of Grand Central & head west to Madison Ave & 5th Ave for the shops then go to Rockefeller Center where you can go ice skating in Winter or head up to the Top of The Rock. TOTR is the best scenic view of NY, the unobstructed views of Uptown & Downtown are better than the Empire State Building & your photos will capture said building! I recommend heading up the TOTR if you wake up to clear skies in the morning as it generally clouds over at some point of the day. Another tip for not spending the cash is to just go to the Rainbow Room (Bar Sixty Five) for a wine & view behind the glass.
Rockefeller Building is also a commercial building so be prepared for workers & the basement is useful for lunch etc. Radio City Music Hall is next door & worth a tour if there are no particular shows of interest during your visit, worth researching in advance. Radio City is also home of the Rockettes.
If the Empire State Building is a must do be prepared for the lines unless you purchase the VIP pass that will get you express entry to the top. After the Empire State walk west along 34th St where you will hit Broadway & Macys amongst other shops, if you’re able to time things right keep heading west to Madison Square Garden for either a tour, concert, basketball or ice hockey event.
If plans are not set keep walking south along Broadway until you get to Flatiron where you can see the iconic building, rest in Madison Square Park, have Shake Shack or head in to Eataly for some Italian marketplace wining & dining.
Next stop south along Broadway is Union Square, where you will find either the farmers market, shops, restaurants & plenty of Subways to get you where you need in advance to avoid the lines to pretty much everything in New York!