Since the US allows pilots to have multifocal IOLs, it seemed surprising the UK didn't also. So I checked out of curiosity (I do expect to get a pilot's license someday, I started in the past and then got too busy and hand't gotten back to it). The UK's CAA does explicitly state:
"Note: multifocal and bifocal implants are NOT compatible with certification. Monovision is not recommended and pilot would require well-tolerated multifocal spectacles in order to meet the distance and near vision standards. Accommodating lenses may be acceptable following a review with a consultant aviation ophthalmology adviser."
That suggests that the Crystalens accommodating lens might be an option if you'd like to try for more of a range of near vision than a monofocal allows (though that would be an out of pocket cost to get a premium lens). Although it merely says "Monovision is not recommended" rather than saying it isn't allowed, I notice that in their section on presbyopic correction that they say:
"The following types of contact lens correction are not acceptable:
Monovision – this is where the dominant eye is fully corrected for distance and the non-dominant eye is corrected for near. The distance visual acuity in the ‘reading eye’ will often fall below the appropriate acuity standard. It can interfere with depth perception and does not give optimum distance vision."
The fact that they don't allow contacts using monovision makes me wonder if in the future they might ever change things and explicitly disallow monovision with IOLs, or if they'd merely only "not recommend" it (though I guess if they disallowed it with IOLs, then laser correction could get rid of the monovision).
I'll note that their guidance for presbyopic correction indicates that they don't allow the use of reading-only glasses, that all glasses used for rading must include distance vision as well, i.e. bifocals, trifocals or progressives/varifocals.
I will note that their guidance notes that "All IOLs must be monofocal.", and explicitly disallows multifocals. However that seems to merely mean one focal distance (rather than multifocal) since it then goes on to suggest that accommodating lenses can be acceptible. That raises the question of where they stand on the Symfony since it is *not* a multifocal, it merely extends the single focus range farther. If that were of interest it might be worth getting confirmation from them, its possible the ambiguity might mean they leave it up to the examining doctor.. or that it isn't allowed. It uses diffractive optics, which lead some doctors who are more knowledgeable about medicine than optics to confuse it with multifocals, but it is viewed as a different category. The FDA data for approval of the Symfony and the Crystalens actually suggest there may be less risk of problematic halos&glare with the Symfony than the Crystalens (though comparing 2 studies can be misleading since they may ask questions differently and have different patient characteristics).
Your issues with halo&glare likely relate to having required a large prescription. Unfortunately there is no IOL yet which has no risk of halos&glare, even monofocals give problems for some people. The Syfmony does have a risk of halo&glare issues comparable to monofocals, though not as low as the best monofocals like the Tecnis one usually used as the control lens for it in studies. In my case I decided since I was 52 when I had surgery (not as young as you, but still potentially living the results for a few decades) it was worth the low risk since I could get a lens exchange to a monofocal if needed, and if I didn't need it then I'd benefit with for decades with a more convenient range of vision. I was old enough that I did have experience with the issue of losing near vision due to presbyopia, and definitely didn't like the thought of losing even more due to cataract surgery. I'd already been battling it using multifocal contacts, and didn't like progressive glasses.
I recall before I had my surgery that there was dispute in the literature over whether the Crystlens is truly an accommodating lens, even though its placed in that category, or whether rather than actually moving to change focus if it is really merely extending the depth of focus statically. They seemed to have difficulty actually getting confirmation the lens moved at all, though its unclear if its not moving why some patients would see no more near than a monofocal. I don't know if the issue was ever resolved, i hadn't looked into it recently.