Let's say I have a function of the form.
Test[File_,text_]
What would be the most automated way and flexible way to generate an input cell of the form,

such that when you press the File Button and select "C:\\Users\\path\\testing.txt" it autofill with the textual arguments.

I'm quit interested to see what the Mathematica community thinks is the best technique for specifying which arguments should be File Buttons and if it might be possible to incorporate the File buttons with Template Completion. My current code is below, which isn't generalized to all function definitions, but I knew it would be best to attempt to create a partially working solution. I used the following question to help piece a together my partially working example.
MakeBoxes[replacementMarker[a_, tag_], StandardForm] ^:=
TagBox[MakeBoxes[a], tag];
replaceMark[rule_, nb_: EvaluationNotebook[], which_: All,
cell_: EvaluationCell] := (
SelectionMove[nb, which, cell];
NotebookWrite[EvaluationNotebook[],
NotebookRead[EvaluationNotebook[]] /. rule]
) ;
CellPrint[
Cell[
BoxData[RowBox[{"Test", "[",
RowBox[{
ToBoxes@replacementMarker[
Button["Browse",
replaceMark[
file = SystemDialogInput["FileOpen"];
TagBox[_, "replaceThis"] :> "\"" <>
StringReplace[file, "\\" -> "\\\\"]
<> "\""
]
], "replaceThis"]
, ",",
TagBox[
FrameBox["test"],
"Placeholder"]}], "]"}]]
, "Output"]
]