The problem isn't really too many rules. If anything it's exactly the opposite. But actually it's not really a problem in the long run. Over the centuries and perhaps entirely unconsciously, English speakers shed all the baggage of, say, gender in nouns, pages and pages of conjugations for even the simplest verbs, agreements in adjectives and so on. The result is a language that at times can feel a bit all over the place but is also rich in variety; no other language even comes close in terms of vocabulary.