thanks guitar doc.
yes do what you want. but varying your strumming style can add interest to a piece and make it more obvious what you are trying to play
it sounds to me that rather than strumming randomly you already have three different and distinct strumming patterns.
I am interested that all your patterns have an odd number of strokes which suggests to me some varying in tempo within the pattern.
for example the second one is very popular for 3/3 time and waltz
1...2...3
V...V...n
but waltz time isn't very common in modern music so its more likely to be played like this -
1...2...3...4
V.......V...n
similarly the last pattern has five strokes but probably isn't counted as five equally space notes - it might be counted as follows
1...&...2...&..3...&...4...&...
V........V.......V.......V...n...
think about what you're doing - there are lots of other way to play the 3 patterns you suggested
and i suggest you try some simple alternate strumming - you might try eights -its a simple pattern which fits many modern songs and is good for rockier number
1...&...2...&...3...&...4...&...
V...n...V...n...V...n...V..n..
keep rocking...