Hello GalGirl, I'm finding your questions to be both helpful and trying to adequately address, but will try to do so now.
My own consent to practicing polyship is at this point experimental and limited. My wife expressed at the end of the Summer that she'd been desiring to try poly for a few years but hesitated to ask me about it because she doubted that I'd consent, and said that she's prefer remaining mono with me if being poly meant loosing me. After much consideration I told her that while this is not what we agreed to when we married, that I do wish to see her happy and fulfilled so would be open to it in concept, but confessed that I'm not certain if I could accept the reality of it. To that end I agreed to experiment, that is permit her to look and communicate with potential poly partners, so long as she could agree to start slowly, get informed, and to either pause or potentially end the polyships if I found it was not something I could accept the reality of. So far she has taken a slow approach, read some poly articles and books, attended poly group meetings, started communicating with a few guys and going on a handful of platonic outings, which has so far she has enjoyed and I've been okay with.
I'm not sure what you mean by participating in my own polyship with my wife? While I'm not seeking any poly partner for myself and would be pleased for us to resume our monoship, to sound her out, I did ask if she would then be open to my seeking a partner. She responded, that she was surprised with my question and hadn't considered it, but once she had, that at this point she's not ready to contemplate seeing me date another woman, and recognizes that it's not fair, so would hope to once she's settled into a new poly relationship to have a change of heart on that, but couldn't be sure that she'd feel differently even then. So if only she is seeking, it feels like being along for the ride, though she expressed a strong desire of what she calls a "puppy-pile" being the center of attention in a Vee at the same time. This is challenged given my being straight and am unsure if that could work, but understand her desire for it.
I'm struggling to understand your questions about gaps, but will attempt an answer based on what I think you're asking. The gaps I mentioned are aspects she still feels a longing for that I either won't or cannot meet for her. This includes but is not limited to joining her for her religious festivals and rites. While I would desire her to share my perspective on the eternal questions, I realize that is not where she is or is likely to join me, so our relations is very likely until death do us part. I agree that these gaps exist and have offered to mitigate these where possible. These seem to be gaps in her preferences that affect our shared marriage, as I feel no gap that drives me to seek a polyship.
My preference at this point include 1) being true to my own conscience2) keeping my marriage whole and meaningful, 3) seeing my wife happy and fulfilled. I'm still assessing whether all of these are in alignment or in conflict regarding her desire for a polyship is concerned though.
The open relationship model she is suggesting is her being the hinge of an MFM Vee with herself as hinge and we two remaining primary and the new guy as secondary, with the possibility of becoming co-primary. The latter because she feels that would be needed or fair if the Vee she desires were to be closed / mutually exclusive as she hopes. I honestly don't know if that is a relationship model that I could thrive in, but have concerns that it might not. I realize that I like having her to myself and worry that her time with a new guy would feel like it was at the expense of our relationship time and energy. My hope is that I could get along with a metamore sharing the most important person in my life and feel compersion from seeing her benefiting from the polyship.
Your point about why not mattering was helpful as I suppose I keep asking about why she wants this in hopes of meeting of narrowing her / our gaps, but am coming to realize this is not possible. Have I yet clarified your question about conditional consent?
Regarding the four numbered questions: 1) yes she has asked me. We are still discussing how I wish to be treated. 2) I am still assessing props and cons, but have given conditional approval based on the pros, but recognizing that the reality of it could show the cons to be much greater than expected. 3) Yes, 4) Yes, although as long as her dates are platonic and infrequent feel like little has actually changed yet, but ponder how it will once it does.
I am still carefully considering the rest of your post as I do see this as wise advice. Please let me know if my answers generate additional questions or concerns?