Most of the units in civ4 have been done pretty well, they all have there jobs an roles, some changes were made to the upgrade paths in warlords an new ones have been added in for bts which by an large the changes/additions slot in very nicely
Marines & sam infantry used to upgrade to mech inf, everyone complained about this and in warlords they no longer upgraded, this was ok an gave more late game unit variety but had a fundamental flaw in my opinion, an that was the units were designed in the beginning to be made obsolete later, so they were'nt really that good a choice after mech inf became available.
Now BTS fixed one of those problems with the new mobile sam unit, which is worth getting after mech infs as it has some good features in it's own right an the str rating has gone up from a competely uncompetive in the late modern era 18 to a better 22, + extra moves + good intercetion.
Problem is that marines have no real role, post mech inf, late modern era.
Mobile Arty usefull as bombards
Gunships are fast raiders lots of moves + good v tanks
Tanks are the main front line assault units
Mech inf is the main city defender an becuase of def terrain bonus's + a little air intercepter power makes a good stack defender field unit too
Mobile sam offers great Air def and has a useful role in a stack, city thats getting bombed, or when fighters cannot give you anti air cover
Para troops are great at dropping onto strong def terrain an holding postions, or pillaging good tiles resources that are further behind enemy lines (still think that being a unit that is effectively jumping out of a plane, there range should be extended when stealth bombers become available as theres a big differance in range between WW2 bombers an modern era equivalents)
Marines seem to get left behind in this stage, since they offer nothing in the later modern era to justify them not being obsoleted an upgraded into mech inf, which is probably why in vanilla civ 4 they did just that, now i personally would not like to see it go back, i liked having the extra choice in warlords, and BTS has solved the problem of the Sam Infantry not offering the required level of performance by offering a later varient with features an performance that ensures it's has a viable role.
So they could either offer a later marine varient, styled into a more commando type role, the unit does'nt need more more str neccessarily but features an upgrades that keep it competive.
Or they could allow marines to be upgraded with the city raider promo, after robotics is researched, Gunpowered units dont get this upgrade, since this is not really there intended function in the game, and i like the combined arms approach to civ 4 warfare, however by giving marines this upgrade later in the game when modern, armour etc is available you wont upsett that balance, but will give marines a good role as cheaper city raiders, since tanks cost a lot more an have no terrain def bonus's, marines would thus still have a use in the late game, being less expensive and a good jack of all trades unit, not as good as tanks or as strong as mech infs but combining some of each units useful attributes, the city attack bonus's that make tanks good assault units, an the abilty to take advantage of def terrain.
Marines & sam infantry used to upgrade to mech inf, everyone complained about this and in warlords they no longer upgraded, this was ok an gave more late game unit variety but had a fundamental flaw in my opinion, an that was the units were designed in the beginning to be made obsolete later, so they were'nt really that good a choice after mech inf became available.
Now BTS fixed one of those problems with the new mobile sam unit, which is worth getting after mech infs as it has some good features in it's own right an the str rating has gone up from a competely uncompetive in the late modern era 18 to a better 22, + extra moves + good intercetion.
Problem is that marines have no real role, post mech inf, late modern era.
Mobile Arty usefull as bombards
Gunships are fast raiders lots of moves + good v tanks
Tanks are the main front line assault units
Mech inf is the main city defender an becuase of def terrain bonus's + a little air intercepter power makes a good stack defender field unit too
Mobile sam offers great Air def and has a useful role in a stack, city thats getting bombed, or when fighters cannot give you anti air cover
Para troops are great at dropping onto strong def terrain an holding postions, or pillaging good tiles resources that are further behind enemy lines (still think that being a unit that is effectively jumping out of a plane, there range should be extended when stealth bombers become available as theres a big differance in range between WW2 bombers an modern era equivalents)
Marines seem to get left behind in this stage, since they offer nothing in the later modern era to justify them not being obsoleted an upgraded into mech inf, which is probably why in vanilla civ 4 they did just that, now i personally would not like to see it go back, i liked having the extra choice in warlords, and BTS has solved the problem of the Sam Infantry not offering the required level of performance by offering a later varient with features an performance that ensures it's has a viable role.
So they could either offer a later marine varient, styled into a more commando type role, the unit does'nt need more more str neccessarily but features an upgrades that keep it competive.
Or they could allow marines to be upgraded with the city raider promo, after robotics is researched, Gunpowered units dont get this upgrade, since this is not really there intended function in the game, and i like the combined arms approach to civ 4 warfare, however by giving marines this upgrade later in the game when modern, armour etc is available you wont upsett that balance, but will give marines a good role as cheaper city raiders, since tanks cost a lot more an have no terrain def bonus's, marines would thus still have a use in the late game, being less expensive and a good jack of all trades unit, not as good as tanks or as strong as mech infs but combining some of each units useful attributes, the city attack bonus's that make tanks good assault units, an the abilty to take advantage of def terrain.