This laid a solid foundation for the series to build off. The tried and tested gameplay of Fire Emblem is all here from breakable weapons and permadeath to grid based maps and recruiting characters during battle, FE1 offers a compelling experience.
Unfortunately it hasn't aged as well as time goes on. If you started with something like say FE7 or later, you're going to miss being able to see enemy ranges and combat forecasts. The lack of being able to trade weapons and items as well as requiring Marth to visit villages also slows down the flow of maps despite them being pretty well designed.
It's a solid first entry but also one that has all the quirks of being the first entry