It's my problem with there not being classes in Skyrim. You become reactive rather than (being forced or encouraged into) having a plan. It's very easy to think "oh look, I've got this cool axe but I can't use it cos it's too heavy so I'll stick points into strength so I can use it" and then "oh look, a cool spell but I can't use it so I'll..." etc etc. You end up with a character that is nothing in particular.
It's better to play in a certain way, you have to adapt, it makes you think.
With this game though you need to be able to switch it about... or maybe need is the wrong word... it gives you an advantage. Some bosses will attack with magic or fire or be vulnerable to lightning and so you can change your armour, weapons etc to combat that or take advantage. You could probably still do it without that but it would be a lot more difficult.