Yeah I agree with that point about tinkering. There were flaws in that German team: midfield, as evidenced by the fact that Lahm, one of their greatest defenders, was shoehorned into midfield; they had a void at left back; no world class striker; lacked quality wingers, etc. I honestly think they were bailed out by having a few phenomenal talents. Collectively, they weren’t special, and I feel that Khedira and Draxler starting and getting significant minutes in that team supports that point.
Lahm started to play as a right back after Mustafi's injury though and it killed two birds with one stone: Lahm contributed much more to the team playing there
(becoming the best right back since then), and Germany gained more quality in their midfield with Schweinsteiger, Khedira
(Özil as an option in the center) and Kroos. They were quite dangerous in aerial game especially thanks to great positioning sense of Müller
(great WC) which rather makes up for a real top-class striker, and they never seemed to lack quality playing on the flanks. By the way, that German squad demonstrated a lot of mental strength and collective excellence to set the pace of the match when it was necessary. You brought one good point though, when you mentioned the left back shortcoming. However, as far as you can see, their reputation is absolutely well-deserved.
NOTE: My observation has nothing to do uniquely with their 7-1 match.
EDIT: As to Spain 2010...
Apain 2010 were good but astonishingly boring. 7 goals all tournament, terrible.
Only 7 goals, but keep in mind they hardly lost the control of match and created many chances to score in that tournament. IMO Fernando Torres was the main responsible for that negative retrospect since he was nowhere as good as he was in EURO'08. Pedro Rodriguez replaced him against Germany and Holland and it was undeniable Spain stepped up its game since then.