I've expressed my thoughts on Archer before which is basically that I like a 155 under armour SP with decent range. I'm neutral on the issue of tracks and wheels (my leaning towards tracks goes mostly for IFVs operating with tanks - artillery matters less which way it goes albeit my preference for tracks with guns has more to do with platform stability and added cross country mobility which matters in systems that need to shoot and move frequently. I think the strategic mobility that wheels are supposed to give is an overblown factor - I prefer better tactical mobility.). My main criticism of Archer is the limited on-board ammo holding and the previous ammo replenishment limbers which I see as not tactical, not protected nor efficient enough to do the job. That can obviously be changed.
I like the idea that the Brits are doing something to to replace the AS-90s sent to Ukraine. In fact I don't think that was a necessity but just a good decision. The UK has 89 AS-90 (per Wikipedia) and has only two 18-gun regiments that use it (1 RHA and 19 RA). There is an indication some places that 104 RA in 1 Arty Bde may be an SP regiment but 104 RA is a reserve regiment with 105mm L118s. IMHO if it is to become SP it won't have "deployable" SPs but rather will be paired with the two RegF regiments and provide trained manning to fill out 1 RHA and 19 RA. So, all in all, the UK has 36 designated operational AS-90s which means that the 30-32 AS-90s going to Ukraine do not need replacing as they come out of surplus stocks created as a result of previous force reduction. That leaves the UK with roughly 21-23 AS-90s as surplus which is probably just enough to cover VOR replacements and training vehicles at the RSA but leaves no viable stock of operational spares or sufficient guns to equip 104 RA (if equipping them is even part of Future Soldier - I couldn't find confirmation one way or the other).
The Brits still have a project to replace the 30-year-old, but modernized, AS-90s which leads me to believe the Archer purchase has two main purposes: to take advantage of an available system to politically fend off arguments that the government is weakening its force for Ukraine and to have one regiment which can experiment with, develop experience with, and build the necessary TTPs for a more modern artillery structure based on longer range, better automated 155 SPs.
I still lean slightly towards the tracked SPs (either M109A7/M1299/K9 albeit, I still think the jury is out on the L58 format for the M1299 barrel - it strikes me that it may be a bridge too far as a practical gun - OTOH I think the L52 barrel (like on the K9) is fairly proven and robust - OTOH again, I think that the L39 on the M109A6/7 is barely adequate and needs to move to an L52. - I'm ambivalent on autoloaders - they add weight and reduce on-board ammo) I gravitate towards the M109 because of manufacturing scale and North American location - it greatly simplifies sustainment and compatibility with the US. I just wish it came with an in-production L52 barrel.
I'll add one additional factor. I think our artillery needs to seriously get on board with mixed systems of guns capable of firing a variety of natures (including illumination, smoke, and cheap dumb rounds as well as some guided precision natures) and longer range (yet cheap) steerable systems for precision work (whether those are steerable rockets or loitering munitions (both on multi-barrel launchers) is a toss up to me at this time and IMHO would depend more on gaining practical experience with both systems rather than just looking at glossy brochures).