Eighteen years. Wow. You are basically a professional dancer. Professional dancers should be able to 1) be able to perform or compete at a high level 2) teach and 3) dance socially.
One thing I left out in my earlier comments is the people who have been dancing for a long time can inadvertently intimidate newbies - particularly for ballroom - because at the dance club they see these really experienced dancers glide across the floor - and they think - how can I dance with these people who are so good and/or dance on the same floor. The nicer dancers will ask newbies to dance because they remember when they were starting out, in simultaneous awe and intimidation.
Another dance hack, especially for Latin dancing, is understanding the structure of the music so that you can predict changes in the music with good probability.
For example, in Salsa music, listen for a change in the music, count 8 measures and anticipate a break, and if there is no break, count another 8 (16 total) and anticipate the break. Sometimes it gets to 24 before there is a break and followers love it when you can predict these breaks (dance to the music).
It is actually a lot, lot harder to do this when you are social dancing and trying to protect your follower (crowded dance floor) - but it is doable.
The other part is tempo changes - vary the speed of your moves to the tempo and feel of the music. Slow things down, speed things up.