I enjoy a nice cup of tea, and I think to have the best cup of tea, don't use tea-bags, use loose tea, and buy a good brand or blend like Twinings Assam or Breakfast tea.
It's a false economy to buy cheap tea, because you can use less of a more expensive leaf, and let it stand longer to get the strength and the flavour.
Another important factor in making a good cup of tea is to always use freshly boiled water--the oxygen bubbles help with the brew.