I don’t think that showing more than 10 completed games would be necessary – I, personally, would not want to trawl through previous games to see the scores (it might be of use, to see what words were particularly high scoring but, in my opinion, this would be quite academic and frivolous). Other readers of this forum could well have other thoughts!
The game is absorbing and fun, for those of us who enjoy word games.
Your suggestion of having a leader board, comparing best scores compared with other players, is a good idea. I’m sure that other players would like to know how their word knowledge compares with others ‘out there’. The leader board idea would make the game more challenging, as the player would now want to outdo others as well as beating his/her own top score.
Look forward to any changes you make – keep up the good work.