52 Ancestor in 52 weeks

#52ancestors I joined a challenge to post something relating to one of any 52 ancestors per week for 52 weeks. Here goes week 1 - topic Start - I chose to start with one of my brick walls that is opening up - Hersch Oks AKA John Oaks or Ocks.
Today I want to share that I have made one step further in breaking the brick wall for Hersch Oks who arrived in NY as a 17 year old in 1911. I was able to find three census records for him that show a name change to John Oaks or Ocks. The 1920 census of Scotts Bluff, Nebraska shows him living at 1706 Twelfth Ave apt. #402 with his wife Mary (surname unknown) a son Albert 5 yrs old and a son Fred 3 1/2 yrs old. This one shows him as being 24 yrs old (meaning in 1911 he would have been 9 yrs old). But it also shows him as arriving in 1915 not 1911 which would put him at 21 not 17 as listed on the ship manifest. Note he was born in 1894.
In the 1930 census of Cook County, Illinois he was living at 330 E 136th Place apt. #181 with a family of Henry Manweiler, his wife Kate and children William 23 yrs old, David 19 yrs old, and Helen E 5 yrs old. It also shows him and his son Fred living with them as boarders. It says he was 36 and Fred 13. So ten years prior Fred was 3 1/2 and is now 13. But John was 24 and is now 36. One of these is wrong. This one shows him arriving in 1913 putting him at 19. It shows him working in a cement block company. The 1920 one had him working at a sugar company. The third census for 1940 in Wayne County, Michigan shows him with a wife named Hazel. He is now listed as 43 (this should be either 44 or 46 or ?) and is now working as a paint sprayer in an auto company. He is living at 15875 Alden Avenue, Detroit, Michigan. Neither Albert nor Fred are listed here. There is still work to be done on this but this breakthrough leads me to seeking marriage records for him and Mary and him and Hazel, looking for Albert and Fred separately, seeking naturalization and name change papers etc. I can think of all the things that need checking but what should I do first?