Depends on what you are attempting to do really.
With my method I can add new towers and tower evolutions, tower types, attack types etc just by adding some new fields into my excel spreadsheet as opposed to creating parent and/or child actors for all the different towers. It makes the initial development a bit longer but in the long run makes things much easier to manage. EG.it took me several days of development to get 2 different towers into my game. It took me another 2 hours to get another 20 in there after that.
Also for balancing it makes things a hell of a lot easier when you just have everything in a spreadsheet and can easily tweak values and lets people that aren’t developing see and modify the values easily too without having to jump into different blueprints all the time.
For mine I use data tables for the towers, levels, enemies, upgrades etc. They are all in a single excel spreadsheet on different sheets with a macro in there to spit them out to the CSV files which are directly in the folder so update themselves as soon as a change is detected. It also lets me setup algorithms directly inside excel to fill in and update new fields whenever a field is changed so that you don’t necessarily have to change everything manually. Simplest 1 is the gold value of a killed enemy, I can get it to automatically fill in the field in excel based on the level, hp, enemy type etc and have that as a static value in the data table so that I don’t need to waste processing time to try and calculate it in blueprints, that’s a very simple example though so the code obviously wouldn’t be tough in blueprints but when you are spawning and killing hundreds of guys it all adds up.