is daily chess the best way to improve overall?

Daily can help with analysis and visualization if you analyze lines without using an actual board or moving pieces, just treat every position as a puzzle, kinda

Damn I hit the button by accident lol but anyway, rapid is still the king of improvement along with tactics (puzzles), cause tactics are 99% of the game up until around 1900-2000. Openings become a little more important around 1600ish and good principles with a light knowledge of openings can take you to that level

Thanks!

It has to be combined with live games for maximum effect if you ask me. Though what do I know lol

As stated above ,daily games can be used as a substitute for classical chess. Also, try playing 30/0 at least once a day. Shorter time controls are excellent for learning openings. I have a different opinion as to what is key to study to improve; I don't subscribe to the idea that chess is 99% tactics, that quote is simply hyperbole to make a point. Tactical success either gives you checkmate, a dominant material advantage that will lead to resignation, or a won endgame. However, if you can't win that endgame you've just wasted all the time and effort spent to arrive at that point. Mastering endgames is the key to advancing from a low-intermediate player to a more advanced player.To be tactically competant, really all one needs do for the most part is to be able to recognize 1 and 3 ply tactics whenever they occur, that will carry you a long way. In analyzing your games, I would concentrate on catching tactical errors up to 5 ply and ignore anything longer.