I was contemplating this issue earlier this morning while doing my dailies. I'm not discussing sPvP as I don't have any experience in that game mode.
When it's time to do Daily Completionist, I 'used' to do as many easy PvE dailies as possible (eg. vistas and gathering dailies) and then head into WvW on my roamer for a quick 5 mins and get the last one I needed. A few months back I decided to store any WvW Rewards potions I earned this way, just to see how long it would take to accumulate 80 (the number needed to complete a reward track from 0 - 20,000 pts), and that prompted me to try and get 4/4 WvW dailies done as often as possible.
As I looked over one of the WvW reward tracks this morning, it suddenly hit me that the value of the daily reward is much better in WvW than in PvE.
In PvE: in addition to crafting materials tied to the type of daily (lumber for daily lumberer, etc), you get 1 Writ of Experience. (https://wiki.guildwars2.com/wiki/Writ_of_Experience)
PvE dailies done in HoT / PoF maps instead reward a consumable that gives mastery XP (which is basically the same thing)
In WvW: in addition to some badges of honor and resonating slivers, you get between 1 or 2 Potions of WvW Rewards (https://wiki.guildwars2.com/wiki/Potion_of_WvW_Rewards)
The disparity as I see it is that over time, the Writ of Experience (HoT/PoF mastery) becomes virtually worthless while the WvW Reward potion will always maintain a high value.
The problem is that Writs can only be used for 2 things:
1- to give an XP bump to a character you're leveling
2- to convert to a Tome of Knowledge and then turned in on a max level character for a Spirit Shard.
As someone who has only been playing for 6 months, I have zero use for either. My characters are max level, I have all my HoT and PoF masteries complete, and I have over 2000 shards in my wallet. If I did decide to level a new character, I already have about 200 tomes of knowledge sitting in my bank already because of WvW rewards. (YMMV)
In comparison, the WvW potions will never lack value to me. I can use them to quickly complete a reward track, which can reward me with, depending on my track choice:
I mean they aren't even comparable in value....
I realize that the WvW chests don't reward crafting mats, but you do get salvageable items from the chests earned while completing a reward track, so I would bet they even out.
One could argue that the PvE dailies are easier and almost completely soloable, but I would refute that, as some of the WvW dailies like Caravan Disruptor and Land Claimer are so easy, any player on any profession can complete them, and do so with a high chance of not even bumping into another player (depending on time of day / server).
Perhaps it is time to re-think the Writ of XP as the daily PvE reward to something that would remain valuable to both new and veteran players alike?
A thought I had was to change the Writ to a lesser version of the Pact Scout's Mapping material (https://wiki.guildwars2.com/wiki/Pact_Scout's_Mapping_Materials), but instead of rewarding 200 map bonus reward points, it instead would reward 100 (or 50?).
Such an item would at least remain valuable to all players, whether those who are accumulating crafting mats for leveling, a Legendary, or for those who want to cash in and sell the bonus map rewards on the TP.