I understand your desire, but, after years of trying, we know that you cannot balance a good PvP with a good PvE.
No one has ever tried to build the systems interdependent on each other. One system was always put in place after another--and at best shared the same stat system, and world. You saying this statement, is tantamount to watching a guy build a house roof first and saying it can't be done because it keeps collapsing. Well, of course, because the house wasn't built to support it yet. It's the same thing with these games, with a world not designed to support both facets, you end up having systems that just weaken the other.
Trying to do half-and-half like you do (literally, as half of your stuff is eternal/unstealable EQ-type PVE looted and half is renewable EVE/UO-type PVP crafted) is going to end up with a weak PVE and a weak PVP.
It's not half and half--you can use a whole suit of crafted, and all mobs will be balanced around that. PvE gives you an augmented edge in PvP, but it's not required for progression. And this is to allow for players to be fluid in terms of which PvE pieces they select, constantly augmenting them as they press the soft cap (The soft cap being in play is another important aspect.)..In some ways, this would be like EVE in terms of every piece has different values as players grow, but with the addition of the PvE gear, you'll add another layer of augmentation, forcing restructering every few levels (If you do your skills right.)...Combine this with the ability to sell old items, and new tiers producing new crafted equipment, and you have a constant churn for the market.
It all leads to constantly needing new gear--yes, there is a limit on this. But that's when you produce an expansion. (Which is how real markets work as well--Think about it, your Iphone 3 doesn't need to magically stop working for you to buy the 4--real markets innovate and that's what new tiers/expansions do.) If you generate new PvE access points and change resource points during these new tiers,
you constantly breed conflict. This conflict, in both progression and control, is what produces strong PvE and PvP.
Then, you have of course the WoW question of balancing gear. How much more powerful is the raid gear than non-raid for pvp? Does it give you a real competitive edge in PvP? If it does enough, then you start getting the snowball effect: the guild who gets the lockdown on raid areas gets the raid gear, which makes it better at locking down the raids, and so on. And you end up with an unassailable position for the rich who get richer, and the rest who can't do much about it and say "sod it". So, your raid gear can't be that much more powerful than non-raid, which weaken your position of raid gear being very rare (if it's not powerful, no one cares about it). It literally has to be balanced on knife's edge to be good... and we all know how likely designers are going to get that right, do we?
Yes, it gives you a competitive edge. As for the lock down effects..Understand, again, the entire game is designed around these concepts. So you'd have some core principles in play.
1.) (PVE Snowball effect) Mobs would be difficult in terms of organization and efficiency, not in player skill. We're talking far less scripting and more focus on time investment through clear times, or restricted access. So more gear wouldn't put a lock on progression in PvE.
2.) PvP Snowball effect) Your map would be designed first off to spawn these resources in disparate spaces, making the control of one guild impossible unless they had a massive alliance. In which case you're still foisting all the political drama of guild cooperation on people.
Also, there would be multiple avenues of gear acquisition (Which should hopefully be easier to do as boss design should be much less complex, except for the highest tiers of PvE). The measuring stick would not be who gets the items, but rather who risks the least amount of time to acquire. So you could LFD from town, go to a dungeon with a group and instance it up, but the drop rate on powerful items there would require more repetition than the drop rate in a community dungeon. ALSO the items acquired in instanced zones, would be BoP decreasing their overall value (BUT access would be there to prevent snowballing). Community dungeons would be fully tradeable with higher drop rates BUT there would be the obvious restriction on access due to limited supply (But these wouldn't be able to be locked down--again, prevent snowballing). And finally PvP controlled dungeons would have the highest drops, but the most difficult access limitations. (And as you can see, there are a lot of access points...Which leads to 2A)
2A.) There would be no hard coded access restriction on said PvP dungeons, either. The advantage for the guild/faction controlling the land would be things like resurrection proximity, less downtime (Due to higher stats on res) and other advantages. In other words, it would be a translation of "reinforcements" being closer thanks to control. But a good group could still access and hold the dungeon if no one from the controlling guild calls it into conflict. (Resources wouldn't be under this system--for a variety of reasons but this post is going to be long.) This goes back to what I said above, by distributing these and creating multiple tiered access points, with varying time rewards, you create situations where no guild is going to lock this down without a significant portion of the server supporting them--and that's a win from a design perspective anyway, because it breeds drama.
So, again, if you design this system from the ground up--with EVERY system in the game interdependent on it, to "breed" either conflict or cooperation, you can end up with systems that eliminate your scenarios.
The problem is, games aren't designed with this in mind. Games are designed very compartmentalized. PvP is designed for PvPers, PvE for people who PvE...And I have no doubt that's done because their test groups and surveys find that people don't mingle. But if a game were designed from the ground up so the world was interconnected, then you should be able to create the need for systems where people who PvE at least form alliances and friendships with those who PvP--and this is what I'm talking about with ritual involvement.
We've constantly been moving away from that in the MMO genre. Heck, most people don't even realize how "subtle" systems like soulbinding have massive effects on our perception of the world, and our ability to interconnect with others. All these systems (Like soulbinding) were developed to tackle problems born our of fractionate systems where each corner of the game was developed for specific player types. We need to go back, design a game for everyone and then build systems to accommodate that. We wouldn't even know what those systems look like right now, because there has never been a game designed like this. And until you do that, there is no telling what will fail or won't.