AFAIK, there are no rules limiting what tags you may use -- you can make up your own if you like. And people have. Here's what the kernel git says right now:

    linux$ git log | sed -nE 's/^ *([^ ]+-by:).*$/\1/p' | tr '[:upper:]' '[:lower:]' | sort | uniq -c | egrep -v ' [0-9] '
         20 ack-by:
         74 acked-and-tested-by:
     195801 acked-by:
         24 acked-for-backlight-by:
         49 acked-for-mfd-by:
         19 acked-in-principle-or-something-like-that-by:
         21 acked-off-by:
         10 analysed-by:
         47 analyzed-by:
         26 based-on-a-patch-by:
         97 based-on-patch-by:
         15 based-on-work-by:
        128 bisected-by:
         18 boot-tested-by:
         37 build-tested-by:
        147 co-authored-by:
       4779 co-developed-by:
        175 debugged-by:
         60 diagnosed-by:
         11 disliked-by:
         11 eviewed-by:
         51 fixed-by:
         18 fix-suggested-by:
         32 found-by:
         48 generated-by:
         19 improvements-by:
         79 inspired-by:
         18 located-by:
         10 not-acked-by:
         86 noticed-by:
         30 original-by:
        140 originally-by:
         95 original-patch-by:
         44 pointed-out-by:
         14 proposed-by:
         10 reivewed-by:
         22 reported-and-acked-by:
         12 reported-and-analyzed-by:
         77 reported-and-bisected-by:
         12 reported-and-debugged-by:
         23 reported-and-suggested-by:
       3017 reported-and-tested-by:
         21 reported-bisected-and-tested-by:
      58990 reported-by:
         11 requested-and-tested-by:
        363 requested-by:
         10 review-by:
         55 reviewd-by:
        513 reviewed-and-tested-by:
     304543 reviewed-by:
         16 reviewed-off-by:
         67 reviwed-by:
         11 root-caused-by:
         29 sigend-off-by:
         10 signed-by:
        157 signed-of-by:
    2253448 signed-off-by:
         59 singed-off-by:
         54 spotted-by:
         32 suggested-and-acked-by:
         12 suggested-and-reviewed-by:
         17 suggested-and-tested-by:
      15568 suggested-by:
         48 tested-and-acked-by:
         22 tested-and-reported-by:
         35 tested-and-reviewed-by:
      62630 tested-by:
         12 verified-by:

My suggestions are both there (far less often than "Reported-by:", but that's not surprising). I think "Analyzed-by:", "Debugged-by", "Diagnosed-by", "Originally-by:", or "Original-patch-by:" would also have worked.

If you don't filter out the tags with less than 10 uses, there are some fun ones. For example, "You're-my-ding-a-ling-by:" should be used more often. :)