There is a country and western song about having too much fun – the premise being that one cannot have too much fun. Of course the real answer to that is a philosophical one, and varies from person-to-person.
A good friend of mine was visiting from Colorado, and I asked her about her love life. She replied that she has been seeing a guy, but it wasn't going anywhere because he liked her too much. Her answer intrigued me, and I pressed her for an explanation. Essentially, she felt he didn't know her well enough to like her as much as he does. I suggested that when he gets to know her better the problem may solve itself. But on further reflection, many relationships have been destroyed because one person was too needy, too clinging, too controlling, or too smothering.
Dogs come to mind when considering too much love. Some breeds are needier than others. Several friends of mine own golden retrievers – probably the most over-exuberant, in-your-face dog one can own. In my opinion, they give too much love. There is a test for too much love. You lock your dog and your significant other in the trunk of a car for an hour. Then open it up and see which one of them is glad to see you. But that is probably not a fair test, since dogs tend to go with the moment, while people tend to place the moment in a broader context instead of taking the moment at face value.
"Too much" of something is a relative concept. Starving people don't think there can be too much food. Elderly people don't think there can be too much time. Addicts don't think there can be too much of whatever they crave. But for normal lives, the concept of too much (except, arguably, for money) is not a good thing. The English language has created the expression, "too much," to mean just that. It is, by definition, not a good thing.
With that said, I like the idea of having 'a lot.' The tough part is deciding when 'a lot' becomes 'too much.' Maturity is knowing the difference. Success is achieving it.