Thanks guys for your feedback. As to the question of function. I would recommend that the purpose of Auto-recall (AR) be for the protection of
High Level Avatars. Because, high level avatars are the only ones with strategic value. Considering that level 1 and 2 losses are inconsequential, and level 3 losses are a minor concern.
In the previous GW Universe my recommendation was always that players not purchase an AR until the reached level 4 (The rank of Captain in the UEF team). For lower ranks it was almost always preferable to spend those credits on reinforcements (RF), and hence win more battles, avoiding the need for AR in the first place!
As for the function of a Recall Jammer. I would suggest that this device is to counter the certainty which AR provides. The situation where one might build such a device would be in preparation for a snipe attempt. Quite possibly in larger team games. As to your question of whether or not an ACU is equipped with AR, the answer is nearly always yes, for any high ranking avatar. Essentially, the construction of a Recall Jammer will have guaranteed certainty that a snipe attempt will translate into a confirmed kill and death of enemy avatar.
As a countering device I believe that the Recall Jammer should be scout-able (and hence knowable).This is an attribute which your ACU enhancement will not provide. The Question is: How will a player, in the game, know whether his opponent is configured for Auto-recall, or recall jamming? But if the Recall Jammer is a structure on the map, it is possible to verify whether one is being jammed by scouting for it. Furthermore, it is possible for the opponents to "Un-jam" themselves by destroying said structure. The Jammer would simply become another target within strategic level play. So I believe that this technology belongs firmly within T3 gameplay.
The other reason why I suggested that this device be a structure is so that the team building it will incur some economic penalty within the game. For this reason I would argue against making the structure cheaper. Especially considering that teams could pool resources to rush the jammer. Or alternatively have a player dedicated to rushing the jammer while others make a snipe. Of course the costs which I proposed are open to debate. But I think you will find that it would take a single players economy 20 minutes to rush the structure with the costs I indicated. Which is about where this technology ought to sit.
With the alternative ACU enhancement system proposed. A "hit squad" team would consist of 2 ACU's configured for AR, and 1 ACU configured for AR Jamming. The purpose of the two AR ACU's would be to engage in frontline combat, force the issue, and get the kill. While the Jamming ACU would sit back in relative safety and simply exist in the game as a "walking jammer". Hence ensuring that any kills made by his teammates were real ones
I think you will find that the altered meta-game will become highly predictable and dry.