I've been playing Words With Friends, and it's helping me further shape my ideas of what I want Scrabble to be.
It eventually occurred to me that I don't like the bonus squares. Their presence leads me to focus on placing high-scoring letters on letter-bonus squares, and any words at all on word-bonus squares. When a short and boring word hits a triple word score square, it can score far more points than a longer and/or more interesting word.
So I started thinking about getting a physical Scrabble board on which I can just ignore the bonus squares.
And then I realized/remembered that I actually don't like Scrabble's letter-based scoring system much even without the bonus squares.
For me, what makes come-up-with-words games fun is coming up with unusual and neat words. And such words don't necessarily contain less-common letters.
So in my ideal Scrabble scoring system, the plays that would score highest would be (approximately) the least-common words that at least two of the players in the game are familiar with. (And probably longer words would score higher than shorter ones, all else being equal.)
For example, I just played WRIT in a Words With Friends game. It scored 9 points, and that was only because the R was on a triple letter score; otherwise it would've been 7. WRIT is a neat word, and one that doesn't come up very often in modern usage unless you're a lawyer, but it's common enough that I imagine most people have heard it. In my ideal system, that should score a lot more than an ordinary word like, say, MEN played on a triple word score (which scores 21 points).
Then again, I suppose in my really ideal scoring system, there's no actual scoring at all per se (so maybe what I really need is a Syzygy or Bananagrams set: no board, just tiles without numbers). Instead, you just get whuffie from the other players for coming up with cool words.
Or quasi-words. I've written before about my philosophy of Scrabble and my proposed house rules, and I've talked about some variants I like, as well as a fun game of plausible-fantasy-words quasi-Scrabble, but I haven't focused much on one specific option for what counts as a word: allowing anything that all players agree is a word, including foreign words and proper nouns. For example, I suspect most of my friends know the meaning of the word “gracias,” even though it's not an English word; why not allow it in Scrabble?
There are certain standard/default parameters for most American word games and puzzles: no foreign words, no proper nouns, no acronyms, etc. And in most contexts I'm pretty happy with those rules. But I think it would be fun to relax them, at least sometimes, for Scrabble.