If you actually wanted to balance the xp-gain, your best bet would be to just reward time played instead of paying different activities differently. Earn a steady amount of xp as long as you do anything. How and why would mining be worth more xp than killing zombies or the other way around? And if I summon screamers that summon zombies all day or if I stand in front of a stone wall with my auger all day, how is that more valuable or meaningful or productive than exploring the map or placing hundreds of blocks, building a giant castle? Two activities that are not rewarded with xp at all. I mean, of course I can make up arguments for any possible standpoint, skill, risk, resources earned, structures built, square blocks explored - but it is merely a matter of opinion, so every intelligent person has to accept it as an undenieable fact that all activities are of equal worth.
And - btw - any
opinion, that declares one activity more valuable than another, contradicts the most powerful argument for a perk system, which is "freedom".
Speaking of that powerful argument, allow me to weaken it. Also free I am to grab whatever I desire from the creative menu and use the console to supply myself with all the xp necessary to buy every perk. The game, if we'd argue that these are not the rules, could just be designed to allow that or something alike, such as pois all over the map that have an endless supply of every block and item, and instead of a perk system, the player spawns already blessed with all available abilities. So in other words, the freedom that we have if we decide to use what's currently understood as cheating, could simply be created as a regular game mechanic.
But we don't want that. And why do we not want that? Because we want to have a progression. And why do we want to have a progression? Because it feels good to gradually acquire better equipment and abilities. It really is merely a biochemical principle: The game provides us with a constant stream of small rewards that make us a little happy all the time. It's how the brain works, look it up if you're interested, here's
a starting point.
I, and with me it seems a significant number of players, prefer to "work" towards specific goals with specific activities, because I find it rather unsatisfying when I can just stand in front of a stone wall with an auger for a day, level up 10 times and buy ten ranged weapons related perks. Without ever having even fired a gun. It does - sorta kinda - feel like cheating. Just like it does feel like cheating when I kill 100 zombies and unlock recipes for workstations and power tools. How does one lead to the other? Not through logic, but merely by the developers' declaration that it's ok. It feels like cheating - while I know it certainly isn't - because of the disconnect between activity and reward.
There is no real equivalent in real life, but looking for one, this came to mind: It is (usually) much more satisfying to build something yourself, like, say, furniture or a pc or whatever art than to just pick a finished product off of a shelve. One (usually) feels better about oneself if one created a thing oneself, because of the closer connection of one with the thing. One, then, has a history with the thing, one has, so to speak, become one with the thing. A part of it, one's time is in the thing, one's passion. Heart and soul? Very possible. It's that feeling of pride and accomplishment, that is a prominent factor that makes games fun to play.
Another pro-lbd argument that I have not really seen being layed out: When lbd was a thing, I used to start with leveling up the pistol and the club. Which sounds more like a strategy than it is - you would simply find the pistol and the club (and ammo for the pistol) earlier than other weapons, and use them, thus automatically and naturally leveling the skills. In the later game, however, working on another skill that I had not yet leveled, often the hunting rifle and the machete, was "something to do" and indeed a concrete plan and conscious decision. I did not need the rifle or the machete, the pistol and the club were doing every necessary job just fine, but improving with other weapons was another goal, that would "force" me into a a) certain different "playstyle" (using that other weapon) and b) position of "weakness", because the damage dealt was still low in comparison. And of course it would function as an untapped source of rewards, adding more funsies to the game.
I still can work towards goals today, sure, but I can just power towards them with the same old same old that I had maxed out asap within the first week of playing. And if you really want to reach a certain goal, you are highly inclined to use the fastest available method.
Now, of course in such cases, we hear the "but you can" or "just roleplay it"-argument. It's not the same, because during your roleplaying, you are fully aware that you are being inefficient, that a method is freely available, legal and not cheating, that would take you to your goal much faster and/or more convenient.
And efficiency and convenience are yet again two qualities our brains like a lot. Which leads me back to what I said in post #259 in this thread.