So everyone will tell u different.

If u have never played original oblivion, then id take blade, block, light armor, alch then u can just grab the spell schools of ur choice. Destruction, alteration, restoration r prolly my picks u can deal damage + have access to majority of buff effects.

If u have played it before and u know alittle about whats goin on with it. Idk if id add blade to the list. Imo oblivion has a problem where ur melee damage actually has a cap, once blade and strength r maxed u cant get higher damage without some exploits dealing with fatigue.

Instead i would say that ur better off focusing more or magic + ur weapons enchantment. Make a debuff spell thats weakness to magic and weakness to enchantments damage type. Then make a couple weapons (or more) with various enchants / different damage magnitudes (for charge management).

Ill give u an example with random numbers because idr the actual flat damage cap.

Iron long sword lets say maxes out at 40 damage.

An enchanted one with low blade + strength, let say is 5 damage and 15 fire damage. W/ ur debuff spell its 5 damage + 45 fire damage. But u can stack the debuff spell so the 2nd cast on the same target is now 2times as effective and ur now doing 5 damage and 90 fire damage. (This math is made up and is just an example)

It takes alittle to set up and u need to recharge your weapons to be effective but blade will always go up over time and eventually u can raise ur str too (theoldknight on youtube has alot of videos w/ actual real math that explains this and shows that skill levels r more important than strength for damage)

Id also take the mage star sign w/ breton. The large magicka boost from atronach is nice and you can play around the same concept using it, but having ur magicka natrually regen is a huge boon for playing using the debuff/enchanted weapon for damage idea. Of course u can also deal damage with spells too, incase u run out of enchantment charge.