i would consider a new rim if the surface is damaged by corrosion (as it is visible in the pics, the rim is visibly stained) and therefore the vulnerability to cracking makes the rim/wheel not worth the effort of repairing. be sure to pick an overall hard anodized rim if you use disc brakes.

i can't see right now how a particular rim would prevent the nipples from aligning better.

i don't know too much about polyax nipples etc.; they could be of use but i'm not sure, haven't worked with them. they are advertised to press more evenly on the eyelets but i doubt (at the moment) it could mitigate all the problems of having a very shallow angle (much less than 90 degrees) between the rim and the spoke direction.

you need to stress relieve properly as to raise the tension of the spokes to about (i went even over 200kgf but that's another matter, YMMV) for other different reasons.
i would advise to raise the tension to even more than 150kgf after being careful to wax lubricate the nipples and the spokes thread as to insure a friction of even less than 0.1 coefficient. and - i can't stress this point more than enough as it is of so much importance - dial in the radial true with spoke tension variance on the drive side when the NDS are slack and DS spokes are at a medium tension. in my case it was about 70kgf. and if there is more than 0.3mm lateral runout with NDS spokes being slack you could consider adjusting the NDS spokes but this will complicate the measurements, computing or just estimating the balancing of tension variance with radial runout.

so, after you adjust DS spokes at that medium tension in order to not need to touch them again... raise the NDS tension to increase overall tension and indirectly get average DS to high levels (say 150kgf, or even more) then you could grab parallel spokes in your hands and do the stress relieving but be sure to not have residual twist in neither DS nor NDS spokes when you do it. put labels on DS spokes to finish the radial and tension variance tuning from the get go with the labels finishing at being all in the same positions (angle) you put the labels, that being when the spokes had no tension in them. it is of much benefit to the wheel to insure low elastic twist in the spokes for several reasons and it's not a much consuming time stage to do it. mark numbers on them as it will help you keep track on them for measurements and adjusting as well.

you may consider going with a 2x pattern for large flanges hubs. you might mix a 2x DS with a 3x NDS so that the NDS spokes would vary less in tension from disc braking or the torque generated by you pedaling and a high torque motor. the benefit of using 2x DS would be that the high tensioned spokes don't get a large tension +/- when under torque and dynamic loads. habits as to learn to avoid torque by pedaling and braking when dealing with potholes are of use.

i am very happy with a 2x pattern on both flanges but then again... that is because i fixed the wheel by straightening the rim (by plastic deformation after it was bent out of shape) - i have not chosen the spokes setup but adapted to it. the only significant advantage of using the same thick spoke morel (DT Alpine) on both flanges is that they are able to sustain impacts with object hitting the spokes with much larger speed and/or larger mass.

i don't know if previous owners replaced the spoke, i doubt they ever broke. stress relieving achieves spoke permanent bend at the nipples and i guess the factory (KTM) had done an good enough job for that purpose. but i also point out that the setup was both 2x on both flanges.

the last owner had no success in truing the wheel wherever he went to service it. i haven't talked to the guy too much, he was the kind to hide any blame. for example he claimed that if the one of the bolt had stripped in the brake post mount threads of the frame it was a problem the bike had not had prior to me buying it. and i had not torqued the bolt but unscrewed it and had this surprise. the bolt was short and engaged only two threads!

so, given the all too common lack of quality service around... i chose to put into the practice the skills and knowledge i achieved before and after repairing properly the only other wheel i worked with 5 years ago. i had changed the nipples from DT Prolock (aluminum with loctite-like paste inserted in them) for the DT Rev (1.5mm) spokes to be able to be under just a tad less than 120kgf tension for a rim brake front wheel with a DT TK540 rim. shame on KTM for picking those nipples, i highly doubt there were a replacement done. the tension was all over the place, the rim had significat radial runout and the average tension was about surely no more than 80kgf.

so i know my facts and i also practiced. feel free to seek other people's opinions but also try to learn a bit about how stuff works.
https://en.wikipedia.org/wiki/Strength_of_materials