For any of us who have heard a chazzan struggle with the words, it is clear that fluency in pronouncing the words needs to be addressed. A simple bu effective way to do so would be to take the Sephardic approach of saying the whole tefillah (except the amidah) out loud.
Lack of quiet/God centered space
We are all surrounded by constant background noise and activity. Entering the God focused, or meditative space which helps set the tone is a challenge.
A few moments of silence before tefillah (preferably at least several minutes), breathing exercises, or asking everyone to think of something or someone that they are grateful for, are some possible ways to deal with this issue.
Teachers might make use of aggados from the gemara (perhaps with an explanation from Rav Kook's Ain Ayah), Rishomnim such as the Rambam (primarily the Moreh), Rabbeinu Bachya's Chovos Halevavos, Rav Albo's Sefer HaIkarim, and Achronim such as the Mabit, Rav SR Hirsch and chassidic literature, as well as Rav Soloveitchik and Heschel.
Practically this might include putting a tefillah to music, painting a scene based on a Mizmor Tehillim, or writing an essay on the struggles of tefillah or writing their own tefillah, an idea which Rav Nachman (the Chassidic Rebbe, not the Amora) suggested.
Practically, a teacher might get up to tell how they deal with the difficulties of davening with kavanah, a student might tell a story, or discuss a strategy that works for them. Inspiring speakers could be brought in from time to time to connect the dots on some of these issues.