Pros
Culture is awesome. Alight hires smart people that they trust to make decisions on their own, so there is plenty of flexibility and autonomy. The product they have is extremely innovative, and there's not a whole lot of competition that can really compete with Alight. The long-term outlook of the business is really good, and the owners are very focused on running a solid business while keeping their people happy and growing. The people that do best here are not afraid to jump in and make things happen, and also are not "above" doing the grunt work it takes to meet client expectations. At Alight, everyone is always willing to jump in and help someone, even if it's not their job.
Cons
It is an agency, and client needs are top priority. This sometimes produces times when workload is significant and it can be very stressful at times. Alight is also a place where you're expected to jump in and get your hands dirty, so if you don't have the "get it done" mentality, it is hard to excel in the culture. This is definitely a place for high performers. Also, if you don't like change, you will not like Alight. Because of the innovative nature of the company, change will always be a part of this world... Out of necessity to keep ahead of the industry.