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Joe_G.Joe, Joe, Joe, . . . . can't you just decide to collect another team? 
The Detroits are neither easy nor difficult; they are somewhere in between (in comparison to other OJs). Thankfully, the largest grouping of Detroits are found in the 1887 leading "0" numbered series which are amongst the more plentiful OJs. I've upgraded most of my poses two, sometimes three times so the cards are out there (several of them now in your collection). Many of the 1887 OJs can also be found as GQs (Gypsy Queens).
Approximately half of those 1887 poses were re-issued in 1888 and joined the new for 1888 Detroit cards of Baldwin, Conway, Getzien, Scheibeck, and White. The players represented in 1888 (be it new for 1888 or re-issues) can also be found on Old Judge Cabinet cards.
Lastly, there were several players found on 1889 cards, all of which played for the International League Detroit Team (the National League team disbanding after 1888). I would say the 1888 re-issues, the new for 1888, and the 1889 International League Detroit cards are all a little more difficult than average OJs.
The toughest Detroit card would be what is catalogued as the McCreachery, M'g'r - Indianapolis card. It is actually a portrait of Deacon White and may be unique. Outside of this card, the others are attainable, especially if only one pose of each player is desired. Going after all the poses (minus the McCreachery error) would probably be a life long pursuit that would end short of goal, but that's half the fun. You have to be very patient. Collecting OJs by pose, even if only a single team, requires a strong will that isn't easily frustrated over the years.
Best Regards,
Joe Gonsowski