Grant respected Thomas, too. An older General, who I believe taught at West Point when Grant was a student there. But Thomas was a bit too slow and cautious for Grant at times.
Grant has a lot of parallels with Eisenhower: Both were West Pointers who came to lead the Army during War (and indeed were important in winning their Wars). Both emerged from war and became immensely popular because of their leadership roles in the war. Both were easily elected President for two terms, and served admirably as President--in my view. Both were able to do things they couldn't have done without their considerable popular support.
Along with a handful of others (Washington, Jefferson, Lincoln, FDR), I regard them as among the greatest American leaders. I have always envied Eisenhower for his personality--he took after his mother, and resembled her the most of his 4 brothers.