Unless the enemy throws something really nasty at us, I would say that we need to start working on ships next year, mostly to fuck over their supply lines as we advance back into the jungle.
A motorcycles are the lightest, fastest vehicles in Forenia at the moment. If we're lucky, our boys might be able to circle around and disrupt their supply lines with them. With all the roads they've created I'm guessing both their infantry and their mechanised units will want to stick to them. Less crawling through mud and tiger attacks after all.
I think a new fighter design to push our air superiority further would be very useful, but a new HMG needs to at least be considered. So far, we have what's basically a heavy LMG and an autocannon with nothing in-between. If not for our AP rounds, we wouldn't have much of a chance at beating their armoured cars in the Jungle. If they develop RHA, even our AP rounds will become useless since our only small arm bullets are 7.76mm. They can only reliably pierce 0 Armour, after all.
Glory to Arstotzka.
Switch trucks to gathering Oil.EDIT:
A single-engined, all-aluminum monoplane fighter with two AS-1910s in the nose hooked up to a synchronization gear, and two AS-AC18s in the wing(or another two 1910s if the AC18s won't fit.) It should Focus on speed and agility for dogfights, but should also optionally have a couple hardpoints for mounting two small 25kg bombs if an opportunity for ground attack happens.
Having four machine guns would probably counteract its speed and agility. Mounting bombs would increase the problem. We'd also have to design bombs which might make it more expensive.
Glory to Arstotzka.