STX Bob - about the flavour text that's fine, but if you're doing the same thing every round it quickly runs out of steam...
Correct, but IMO flavour text is a way to focus on story not mechanics. Watch a combat run on Critical Role on Geek & Sundry for fun examples.
IMO 3&4e moved towards the idea of really making the combats more fun by focussing on the tactical element of combats above other features of the game (4 more than 3). They both became complex and combats bogged down for hours. 5e does this less than both and is trying to shift focus more to exploration, roleplaying, interaction etc. so they made combats simpler.
One issue in 5e with unlimited decent cantrips is that spellcasters (especially at low level with hardly any spells) can feel a bit boring. This can be the same with other classes but I suspect this lessens at higher levels. I have found players can handle some supposedly tough enemies at quite low levels so my suggestions are:
1. really mix it up. Put in a horde of kobolds (my players fear pack attack), then an invisible stalker
2. give players in combat ability options - scroll of slow, arrow of shatter, potion of fire breath
3. Make combats short & with a purpose beyond combat
4. Focus on the other "limbs" of 5e exploration & roleplaying
Oh and throw in flavour text especially on the big moments.
(Btw I use a system with one use items like potions and scroll to say that each time you use it roll a d4 on a 2-4 the magic remains or there is still some liquid left etc. This encourages freer use of the items and keeps those player combat options available longer)