Layout is important but that boat has sailed for you as did for me on my first real rifle.
Firstly......
I personally can live with a long pull on the front trigger. What I can't live with is a miserable and heavy break after the long pull.
If the front trigger trips the lock time after time but is heavy, most of that can be overcome by tuning the lock. You need to tune the lock anyway for optimal pull.
Caution... It's real easy to go too far. Maybe an experienced hand is best here. The difference between just right and too far is Oh so slight. It's a balancing act. This is
real gunsmithing.
There is no reason why the front trigger on a double lever set, should not have a good decent pull. Again a long pull to take up the slack is OK but it should have a good crisp break after that long pull, A hunting trigger.
So if it trips the lock reliably but with a heavy pull, consider tuning the lock.
Secondly...
There's a lot of tuning you can to the triggers themselves. Polishing the foot of the mainspring, polishing all the friction surfaces and tuning it just right. There's a lot of adjustment just in the trigger's mainspring tension. So the triggers can and need to be tuned as well.
Caution... Be careful with the notches just like you did with tuning the lock. It's easy to go too far.
Try this and you may be surprised.
Botched Gunsmithing... Bent sears and soldered up trigger plates, choose your poison.
Don't use brass for this "fix". Both bending sear and soldering on material bespeak of covering a mistake and fixing a boo boo.
I chose to bend the sear. I didn't like it but...
It must be done red hot with a quench ready and it is a compound bend. The jaws of the vice act as a heat sink so the sear cog should be OK. It's a good idea to lay out and know how far you need to go. And.... sears are replaceable
.
I don't liker either one of those fixes but it is my personal rifle. For a customer, this is substandard work.
This why I think a long but decent trigger is better than either one of these options. Lastly....
Trigger position and new parts.
Are the triggers in position for optimal operation? Does the sear split the V between the trigger blades? The adjustment screw should be straight below the sear bar. If not, you can always move the triggers fore and aft and repair the inlet if you need to. You can also sink the triggers in their inlet a little and still be OK.
Making a new front trigger...what a pain...Honestly I would consider building a new or buying another set, maybe a single lever double set..but that style was really the correct type for my rifle.