While some would argue, the original 1st Gen LSE was the best externally. They had a special body kit designed by some company that was into that sort of thing and included a lip spoiler. There were special interior combinations I believe and only certain interior colors. It was a given it had elements of the sport package. The most noticeable feature of the LSE is the "Round Fog Lights" and dual exhaust tips. The 2nd Gen LSE had a different type of kit but still with a lip spoiler. The side skirts weren't flared the same as the 1st Gen, it only had single exhaust tips , it differed relative to other 2nd Gens by having all red tail lights(no amber turn signals. Up front they still had round fog lights but they are spaced farther apart and are aligned with the low beams. During the 2nd Gen years, there was an LSE Appearance Package available. The rest is just badges and I think some special suspension tuning. Lots of guys on here have done conversions so I guarantee you I don't know what I'm talking about compared to them.
For the record, I have a 2006 which looks like the 2nd Gen LSE without the lip spoiler, the LSE badge, and with amber rear turn signals.