M#$%&"()*+H-./0e1234l5678l9:;<o=>?@,ABCD FGIJWKLNOoPQRSrTUVXlYZ[\c^_`b"dfgh]ikmn'pqst!uvwxryz{|a}~jE

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M    "    H    e    l    l    o    ,         W    o    r    l    c    "    ]    '    !    r    a   j 

M                      Increase the step count from 3 to 5
 "Hello, Worlc"        Push the string to the stack
               ]       Increment c to d
                '!     Push !
                  r    Reverse the stack
                   aj  Jump back to the 10th character
  H                    Halt and output the stack

M#$%&"()*+H-./0e1234l5678l9:;<o=>?@,ABCD FGIJWKLNOoPQRSrTUVXlYZ[\c^_`b"dfgh]ikmn'pqst!uvwxryz{}a|~jE

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M    "    H    e    l    l    o    ,         W    o    r    l    c    "    ]    '    !    r    a   j 

M                      Increase the step count from 3 to 5
 "Hello, Worlc"        Push the string to the stack
               ]       Increment c to d
                '!     Push !
                  r    Reverse the stack
                   aj  Jump back to the 10th character
  H                    Halt and output the stack

Backhand, 109 - 95 = 14

"#%d&+e-.H/0l12n34,56 8;W<=p>?r@A"BCrDE)FG$IJoKLoMN:OPoQRoST]UVoXYoZ\o~_o`a[bfoghoij9kmcqs*tuo7w(xyoz{'|}!^vH

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Note that the version on TIO is missing a couple of instructions (notably '). You can see it working by bundling it with the interpreter here. This program works because Backhand executes every third instruction by default (it's actually a little more complex than this), so the actual code is more like:

"  d  e  H  l  n  ,     W  p  r  "  r  )  $  o  o  :  o  o  ]  o  o  o  o  [  o  o  9  c  *  o  (  o  '  !  H

However, since you can't remove the spaces inbetween without breaking the flow of the program, you can replace them with whatever you want. It's possible you might be able to form a valid program from that mishmash, it is unlikely. The duplicate characters come mostly from having to pad out the program above 95 necessary characters, using the os needed to output each character (though H would be able to substitute for those too).

Backhand, 100 - 95 = 5

M#$%&"()*+H-./0e1234l5678l9:;<o=>?@,ABCD FGIJWKLNOoPQRSrTUVXlYZ[\c^_`b"dfgh]ikmn'pqst!uvwxryz{|a}~jE

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Note that the version on TIO is missing a couple of instructions (notably '), so I've copied the interpreter here. This program works because Backhand executes every fifth instruction thanks to the first M (it's actually a little more complex than this), so the actual code is more like:

M    "    H    e    l    l    o    ,         W    o    r    l    c    "    ]    '    !    r    a   j 

However, since you can't remove the spaces inbetween without breaking the flow of the program, you can replace them with whatever you want. The final check is that the j jumps to the 10th character (H) to halt and output,, which is less feasible if you modify the program. It's possible you might be able to form a valid program from this mishmash, but it is unlikely, and I'm sure that there's another permutation that fixes that.

Explanation:

M                      Increase the step count from 3 to 5
 "Hello, Worlc"        Push the string to the stack
               ]       Increment c to d
                '!     Push !
                  r    Reverse the stack
                   aj  Jump back to the 10th character
  H                    Halt and output the stack