I have found that the biggest improvement in taste comes from using freshly roasted beans. Freshly grinding those beans comes a very close second. That is to say, freshly ground stale beans still taste stale. Pre-ground fresh beans still taste OK after a week (but won’t be suitable for an espresso machine.)

The biggest difference in taste comes from selecting specific beans and roasting them carefully. You may or may not find it an improvement. It seems most supermarket coffees are selected to have the same kinds of taste and I find them nearly universally bland. When I make coffee for other people I get a 50/50 split between those who immediately notice an enjoyable difference from supermarket coffee and those who don't care. Personally, I find instant coffee very unappealing but some people enjoy the taste of that too.

I think the closest comparison is wine. Nearly everybody likes wine and accepts that different grapes (beans) give different flavours. Most people agree that the very, very cheap wine often tastes like silver polish. The remainder may or may not then have a preference between a £15 bottle and a £5 bottle. Those who do then may or may not differentiate between specific qualities of those wines.

I'd suggest buying a bag or two from a speciality roaster such as www.hasbean.co.uk Get it pre-ground and see if you prefer the difference. If you do then consider getting a grinder for another leap in quality.

The same website has a brew guide for the moka pot – it’s a great way of making coffee and everybody uses it differently. You might enjoy experimenting with it.