Hey, you know what? Good speakers and writers are hard to come by. Oh sure, there are 10s of millions of writers in the world it seems and with the Internet there are more and more every day. With YouTube there are more and more speakers throwing their hat into a video as well, but it seems that there are very few "really good" writers and speakers.
If you are sitting in an audience and a speaker is making you laugh, and their timing is perfect, and you can tell they are throwing a little improvisational in from time to time, it makes you listen, and wonder what they're going to say next, and you don't want to miss anything.
You might think this is hard to do, but it really isn't, and, you may even speak this way when talking with your own friends, and not even realize it. Now you might occasionally strike a sarcastic tone, and do a little Impersonation of someone that you're making fun of behind their back, and if you do this, and you don't even realize it, you have all the skills to be a great speaker and to throw in a little improvisation, and a little Impersonation.
It's really not that difficult, and perhaps the reason that few people are able to do this, is they are too worried about what the crowd might think, or they don't feel the self-confidence they need to pull it off. Now then, I'm not suggesting that you strike a sarcastic tone, that sort of comedy isn't always good when speaking to professional groups, and yes folks who read articles, essays, other writing probably get enough of that style reading blogs and stuff on the Internet.
However, a little Impersonation can go a long way, and you shouldn't be afraid to try new things, or a little innovation here and there. Sometimes it just feels right, and you should go with it. The best way you can try new things is to try it out on an audience, and then work on and practice the timing. Over the years I've developed about 15 minutes of comedy, all original jokes, which make almost anyone laugh wherever I go, and they go over really good with large audiences.
Is it hard to impersonate people? Generally not, especially celebrities, because they have idiosyncrasies, certain phrases, and a certain voice inflection. It's not hard to impersonate them at all, but it does take practice. I would suggest to you that you should practice these things, and borrow various phrases that people use, and use them in your own writing, of course always attributing them to the person who you are impersonating; try it, it works, and the audiences love it, the readers too. Indeed I hope you will please consider all this and think on it.