You could assign a script to a keystroke or toolbar button.
If, for example, you select a date or number column by clicking on its header (so that the whole column has a blue highlight) the following script will fill the cells of all rows with values derived from those of the first one or two rows.
(The difference between row values defaults to one day (or 1.0) but if row 2 already contains a value when the script is run, the series will continue the interval/difference between rows 1 and 2).
Code:
-- FILL DATE OR NUMBER COLUMN WITH VALUES
-- BASED ON THE VALUES IN THE FIRST ONE OR TWO ROWS
tell application id "OOut"
if (count of documents) < 1 then return
tell front document
set lngRows to count of rows
if lngRows < 3 then return
set lstSeldCols to selected columns
if (count of lstSeldCols) < 1 then return
set {eType, idCol} to {type, id} of first item of lstSeldCols
if eType is not in {number, date} then return
set {varStart, varNext} to {value of cell id idCol of row 1, value of cell id idCol of row 2}
if eType = number then
if varNext is missing value then
set varDelta to 1
set iStart to 2
else
set iStart to 3
set varDelta to varNext - varStart
end if
-- FILL REMAINING CELLS WITH NUMBERES
repeat with i from iStart to count of rows
set value of cell id idCol of row i to varStart + (varDelta * (i - 1))
end repeat
else -- date
if varNext is missing value then
set varDelta to 1
set iStart to 2
else
set varDelta to ((varNext - varStart) / days) as integer
set iStart to 3
end if
-- FILL REMAINING CELLS WITH DATES
repeat with i from iStart to lngRows
set value of cell id idCol of row i to varStart + (varDelta * (i - 1) * days)
end repeat
end if
end tell
end tell