I do remember as a child being gutted by Swansea losing to Barnsley in the play-off final in 2005, despite not really being into football and the team until 2006. Because of when I started supporting Swansea, the highlight/lowlight balance is definitely in favour of highlights.
Guillem Bauza's double against Gillingham to secure the League One title in 07/08 was probably my first major highlight. From then on, Swansea became synonymous with good possession football, and it was great to see the club getting more and more attention for the playing style (even if it slacked off under the likes of Sousa). Beating Cardiff is always a highlight, whether it was in the first South Wales derby for ages back in 2008, or Pratley's volley in a 3-2 thriller and Emnes' twenty-yard strike.
The whole play-off campaign in the 2010/11 season was special. The tightest of draws with Forest after playing with ten men for eighty-eight minutes in the first leg, and a second leg that featured a belter from Leon Britton and Darren Pratley scoring from the halfway line to get us to Wembley. The play-off final against Reading is one of the happiest days of my life, and I frequently rewatch the goals from that game. It's weird but I probably value the play-off win over the League Cup win a couple seasons later, probably only because of the drama that surrounded the match with a 3-0 nil almost slipping, versus a five-nil domination. But still, the League Cup was a fantastic achievement, and I'm glad to have witnessed it as well. Then again, the League Cup win allowed us to beat Valencia three-nil in Spain and take Napoli to the limit. The Premier League era has given me a bunch of great memories with some of the results against top teams.
The lows? Definitely the incompetence behind the scenes over the last few years, whether it's managerial stints, transfer targets, new owners or transparency between board and Supporters' Trust becoming less and less so. The fortunes have changed slightly, but it doesn't excuse the shambolic nature of the club at this current time. It's just a matter of time before relegation happens, and the project of the last decade and a half comes crashing down. Then there's individual lows like seeing Swans thumped in person, losing to Cardiff due to gutless performances or last minute goals, and the fact I have yet to see Swansea win in the last seven matches I've attended, and the last five away matches I've been to.