1: They really should add Air Conditioner animations according to power,it is at 1 so it will make light noise and at max a bit noisy and fast.
2: They should add new engine sounds to DAF XF 105 and Iveco Stralis because they reuse sounds from their future successors which is unrealistic after all. Also they should improve the Scania horn because when Wombat used it in his 1.38 stream it sounded complete unrealistic coz it looks like one of those american air horn sounds you find in free Sfx horns to download sites and in that Kenworth W900L (Linerunner) in GTA 3 and VC.
3: I think they should add modern trucks to ETS2 (Actros MP5,Iveco S-WAY and TGX 2020) and ATS(New Cascadia,W990 and LT) but most of them are like Concept Trucks which you will not see the ai driving many of them as they are in low production yet.
4: They should remove the Old SCS trucks(DAF XF 105,Iveco Stralis,Volvo FH16 2009 and old 2008 VNL,Renault Magnum and Premium and the 1st gen scanias) as they recently went out of production and according to new truck dealers i don't see them from outside the showroom but when you enter,you see them.Maybe they need to add some used truck dealers scattered around europe including only those SCS trucks that went out of production and discontinued.
5: ETS2 DLC i believe the next after Iberia would be the West Balkans,Ukraine and Belarus coz that's the only final new countries to add to finish all the countries addition in Europe which means SCS will now add free DLC and base game expansions and their Islands(Ibiza,Mallorca,Ireland,Faroe Islands,Malta(please no Mario
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Now from now on discuss also your own suggestions here excluding mods.